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  1. #1
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    Mach 6 Frame size

    I'm about to order a Mach 6 frame from my LBS, I'm going back and forth between Large and Medium frame size. My height is 5"10".
    Pivot's frame recommendations-
    Med- 5'9"-6'
    Large- 5'11"-6'2"

    I have been riding a large frame firebird even though its recommended for 5"11" and up. The reason is that I don't like how bikes handle with a long stem and I don't want a medium with a long stem. I also (maybe just in my mind) feel like I have a little more stability during high speed descending which is my 1st priority when bike shopping. Right now I'm leaning toward a medium but I just don't want to have to have that long stem on it.

    What I'm wondering is- can anyone here who has been riding their new Mach 6 shed some light on how they like their frame size for their height?

  2. #2
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    I am the same height as you and got a large. I rode the medium and it felt tight even with the 70 mm stem they ship it with. Unless you want a BMX style setup I would go the same direction.

  3. #3
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    I'm happy with a large at 6'1"; long legs, shorter torso. I'm currently running a 70mm stem, 750mm bar. Yesterday's ride had a lot of steep up/down switchbacks and punchy climbs, and I had the room I needed to work the ups. All other aspects felt great as well so I'll run with it.

  4. #4
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    Thanks for the replies so far. You guys have me leaning towards the Large frame/short stem. I think I'm right in that tricky 'goldilocks' height where its right between medium and large. I won't have a chance to demo before buying so I'm trying to gather all the intel I can.

    I'm so excited about this bike that I kept waking up last night thinking about it! Mach 6 be causing insomnia!

  5. #5
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    Well, if it is any consolation, your excitement and lost sleep over the Mach6 is completely warranted. Sooo much fun! I'm really glad I had multiple days off to throw a few different types of trails at her right off the bat.

  6. #6
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    Further update- now back in the medium camp after thinking it over a bit more and sadistically obsessing over every review and comment I could find in this forum and other reviews.

    The guy who wrote this is just under 6' tall-
    "The medium size felt really good. I suspect I could’ve fit fine on the large as well but the medium felt playful and compact without feeling cramped. I took to it immediately."


    Also the length of the top tube on the medium is only .4in less than the large Firebird, I have a very short stem on my FB so I can have a similar one here or a touch larger and it'll probably feel like home with less weight. Salespunk makes me a little nervous since it seems he's as obsessed as I am and he's getting the large but I think I'll roll the dice on Medium. I'm going to see if there is a shop in town that has a medium I can sit on.

  7. #7
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    In terms of sizing, I ride a large HD with an 80 mm stem so I like my bikes more stretched out. I figure my Mach 6 should be perfect with a 65 stem.

  8. #8
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    I'm 5'8" and riding Medium /w short stem (50mm) and it's fine.
    Mach6 top tube is much longer than FB

  9. #9
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    For anyone still interested in this-
    I called around and a LBS had a medium frame (with 80mm stem, standard from Pivot), they strapped on some pedals and I did some laps in the parking lot. It felt pretty close but just a tiny bit too cramped. I know the stem will have to be shorter on my bike and that tips the scales to the large. Bike shop guy said he thinks my legs are on the longer side and that forces me a bit high and over the bars for a medium and I think he's right.
    Final answer= Large Frame

    Its the first time I've seen the bike in person and I must say it is very good looking and seemed super stiff and light. It was an XX1 build with tubes, no pedals or dropper it was only 26.23 on the scale.

  10. #10
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    What's going on with there reach numbers. I'm like 172cm and want to run a 50mm stem. Looking at geo's of kona process 153 and knolly warden these reach numbers look so short. Top tube is about the same. If I want to run that short of stem should I go large?
    Life is like riding a bicycle. To stay balanced, one must keep moving. - Albert Einstein

  11. #11
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    Life is like riding a bicycle. To stay balanced, one must keep moving. - Albert Einstein

  12. #12
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    Quote Originally Posted by thegromit View Post
    What's going on with there reach numbers. I'm like 172cm and want to run a 50mm stem. Looking at geo's of kona process 153 and knolly warden these reach numbers look so short. Top tube is about the same. If I want to run that short of stem should I go large?
    The Mach 6 (like most Pivots) has a pretty slack seat tube angle, effectively decreasing reach for a given top tube length. I haven't heard the rationale for this from Pivot, but I suspect it is attributable at least in part to the inherent antisquat nature of the DW Link suspension.

    Designs like the Kona and Knolly will sink into their travel more when climbing, and a steep seat tube angle helps keep the riders weight from sliding too far back. The Pivot will ride higher in its travel, allowing the front to be more easily weighted under these circumstances.

    I happen to like Pivot's approach, as a) it allows for a shorter wheelbase (long reach/short stems are nice to a point, but eventually the wheelbase can become unwieldy) b) it allows for zero offset seat posts without putting the rider in a TT position at full extension.
    ''It seems like a bit of a trend, everyone trying to make things longer over the last couple of years" Sam Hill

  13. #13
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    I'm coming off a medium tracer 275 60mm stem which rode pretty well. Climbed good descended very well. I was running a -1.0 angleset on a 160 pike so the headangle was 66.5 +or- .2 bb raised a bit somewhere near 13.5 or so. Comparing geo there pretty close but the pivots Top tube is reading longer by .6 than the intense which I want but intended still has a longer reach. I don't get how pivot is coming up with such a short reach.
    Life is like riding a bicycle. To stay balanced, one must keep moving. - Albert Einstein

  14. #14
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    Quote Originally Posted by thegromit View Post
    Comparing geo there pretty close but the pivots Top tube is reading longer by .6 than the intense which I want but intended still has a longer reach. I don't get how pivot is coming up with such a short reach.
    That is odd considering Intense also lists a slack "effective" seat tube angle of 71* I can only guess that the companies calculate "effective" (since the seat tubes do not form a straight line with the BB) seat tube angle, and in turn effective top tube length, differently. Having the reach measurement is very useful in cases like this, and it helps explain why the wheelbase on the Intense actually comes out longer than the Pivot, even though it has a shorter listed ETT and 1.5* steeper HTA.

    At ~5' 8" it seems unlikely that you would want a large, but perhaps not completely out of the realm of possibility. The head tube/standover is only nominally taller than the medium, so if the seat tube length works for you (i.e. it allows you to run your dropper of choice) it might very well work for you.

    One other consideration- if you haven't already it may worth trying a wider bar with a 50mm stem on your current ride (or even just trying the shorter stem by itself) to make absolutely sure you want to make up for the shorter stem with a longer top tube.
    ''It seems like a bit of a trend, everyone trying to make things longer over the last couple of years" Sam Hill

  15. #15
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    I am going to be running 785mm bars. Probably just my 60mm stem and get a medium if I get one. I was just liking what these other company's where doing with long top tube short stem combo.
    Life is like riding a bicycle. To stay balanced, one must keep moving. - Albert Einstein

  16. #16
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    I really can't decide what size to get. I want to ride a 50/40mm stem but fear the 15.8 Reach will make me too cramped. The 16.3 reach is more inline with most the bikes I've been looking at (knolly warden/kona process 153) In my eyes the good for the large is; longer reach, 45" wheelbase the head angle is 66.25 and I already have a pike 160 so I won't dip below 66* the bad/worry is will I fit with my 120mm reverb, I think I will but not sure. I also have 170mm cranks. My friend at the bike shop agreed with me about running a large with the short stem. He's my height and also thinks the medium feels a little small. Anyone with a large running a short stem 50/40mm? If so how tall are you and what bike where you riding before? It seems like every bike in this category has a longer reach. Am I crazy for thinking like this?
    Life is like riding a bicycle. To stay balanced, one must keep moving. - Albert Einstein

  17. #17
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    Quote Originally Posted by Salespunk View Post
    I am the same height as you and got a large. I rode the medium and it felt tight even with the 70 mm stem they ship it with. Unless you want a BMX style setup I would go the same direction.

    What size stem did you decide on and how does it feel?

  18. #18
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    I am on an 80 stem with 1 cm of spacers and it feels great.

  19. #19
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    I demoed the Mach 6 in both a medium and large with a 50mm stem. Being 5'9" with a 31" inseam, I could have picked either size. Neither felt wrong for my height and I liked both, they just felt different. The medium was more playful and the large more stable. I ended up with a medium Bronson and I run a 50mm stem and I'm very happy.

  20. #20
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    I'm 5'11, 32" inseam and ride a large with the stock stem. Feels just fine. Thought about the medium, which I ride in Specialized sizes, but the large felt just fine on the Mach 6 to me. Happy with it
    I have too many bikes, but it's not enough

  21. #21
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    I'm 5'11" with a 32.5" inseam, normal proportions. Took out a Mach 6 from the Bike Co. They calle and me, discussed my riding style and existing bike before suggesting a large with a shorter stem. Took a large with a 50mm stem out to some Santa Ana Mountain chunk and felt really balanced. Can't say "dialed" give the tire/fork setup on the demo fleet but really solid. Walked back in and ordered a large.

  22. #22
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    The Mach 6 has a very short reach when you compare it to the 'modern geometry' bikes (mostly from europe).
    That's what was holding me back ordering one. I had a Bronson and I would have liked it to have longer reach too (but the Bronson is even longer than the Pivot). So the Mach 6 felt of my short list.
    Ibis has the same problems with too cramped cockpits as well I think.

  23. #23
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    I'm just under 5ft 9in and running a medium with 50mm stem. Fits perfect. I was on a Carbine 275 medium with 50mm stem. That fit well, but the Mach6 has a big "sweet spot" to work within. The cockpit feels roomy compared to the Carbine but I never feel stretched out.

    According to Pivot, I should run a small (5"4 - 5"9), but I'm glad I'm on a medium. Maybe their sizing chart reflects the fact that they ship bikes with too much stem.

    I would recommend going with a stem 65mm or less on aggressive trail bikes like a Mach6, Range Killer, Process 153, Bronson, etc. Longer stems seem to work better on light trail or XC bikes or if you won't be riding a lot of steep downhills.

  24. #24
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    Mach 6 size.

    Quote Originally Posted by Throttlemire View Post
    I'm just under 5ft 9in and running a medium with 50mm stem. Fits perfect. I was on a Carbine 275 medium with 50mm stem. That fit well, but the Mach6 has a big "sweet spot" to work within. The cockpit feels roomy compared to the Carbine but I never feel stretched out.

    According to Pivot, I should run a small (5"4 - 5"9), but I'm glad I'm on a medium. Maybe their sizing chart reflects the fact that they ship bikes with too much stem.

    I would recommend going with a stem 65mm or less on aggressive trail bikes like a Mach6, Range Killer, Process 153, Bronson, etc. Longer stems seem to work better on light trail or XC bikes or if you won't be riding a lot of steep downhills.
    I ride enduro, I also cannot decide what size, I am 5" 10, the concern I have with the medium is on steep technical climbs, the slack seat angle will put you over the back wheel when seat post is fully extended, as for cramped position I am not concerned as on descents I am generally standing with weight on pedals. Like the idea of lower. Bottom bracket for my style of riding. I am hoping to test a medium in the next week or so, the large felt to big for me even with 50mm stem.

  25. #25
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    I wish I had one to sit on at least to test here, but I had to order mine sight unseen. I'm 5'8" and both the bike shop and pivot customer service recommended the small. We'll see. It should hopefully be here today or tomorrow.

    From reading this, a medium with a 50mm stem might have been best. I think my legs are slightly shorter than they should be for my torso so who knows.

  26. #26
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    Re: Mach 6 Frame size

    Quote Originally Posted by DaMaDo View Post
    I wish I had one to sit on at least to test here, but I had to order mine sight unseen. I'm 5'8" and both the bike shop and pivot customer service recommended the small. We'll see. It should hopefully be here today or tomorrow.

    From reading this, a medium with a 50mm stem might have been best. I think my legs are slightly shorter than they should be for my torso so who knows.
    Hmm, at 5'8" a Medium should be a better choice, especially if you are planning to run a 50mm stem.
    I am close to 5"9" and the Demo M felt just right.

  27. #27
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    I'm 5'77 with M size and a 50 mm stem.
    It's perfect to me

  28. #28
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    I just got my small M6 and it initially seemed a bit too small until I got back on my medium Scott Spark 960 to compare.

    All of a sudden the Scott seemed even smaller in comparison surprisingly. I know I've been fine on that bike so I think I'll keep the small M6. I won't do the shorter stem yet though.

  29. #29
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    I'm 5'11" 33 pants inseam..long arms.

    - large Mach 6
    - 65mm stem 5mm spacer
    - 740mm bars

    Tried a 50mm stem and the bike was too cramped.
    Safe riding,

    Vik
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  30. #30
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    When seated on the bike and you have your arms, back, and neck straight and you look down, where is the front wheel hub in relation to the stem/handlbar intersection?

    My whole hub is just in front of the handlebar. Not sure if that's right or wrong on an AM MTB.

  31. #31
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    Quote Originally Posted by DaMaDo View Post
    When seated on the bike and you have your arms, back, and neck straight and you look down, where is the front wheel hub in relation to the stem/handlbar intersection?

    My whole hub is just in front of the handlebar. Not sure if that's right or wrong on an AM MTB.
    My hub lines up with my bars when seated on my Mach 6.

    On my Nomad my hub is way behind my bars [90mm stem] and I ride hard on the tech up and down.

    I wouldn't get overly concerned about where the hub is relative to the bars.

    You are going to do all your important riding in the attack position and what matters is where you COG is which is quite dependant on your body type.

    You can move your COG around quite a bit in the attack position so there are a variety of stem/bar positions that can work for any person. It just comes down to what you prefer.

    If your COG is further back you will have to move your body forward to get weight/traction on the front wheel in turns and on steep climbs, but you'll naturally be further behind the front wheel for steep downs/drops.

    If your COG is further forward you will naturally be in a good position for turns and steep climbs, but you'll have to move further back behind the front wheel for steep downs/drops.

    Stems are cheap so grab a couple options and try them out on your local trails to see what you like best.
    Safe riding,

    Vik
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  32. #32
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    Thanks Vik, I appreciate that.

    I took my M6 out yesterday and I felt like I could do a lot more on it than my medium sized Scott Spark. It felt a lot more flickable and controllable in tight turns. I think there's a lot more weight on the front with the small M6 than on my medium Scott Spark. I never knew what would happen in a turn with the Spark, but I had a much better grasp of turns just on my first ride on the M6 yesterday.

    I also just ordered a KS i900-R dropper which has a 20mm setback so that will make a slight change when I'm sitting, although now I'm thinking I probably don't need it.

    EDIT: I set the bike up with two bathroom scales, one under the center of each wheel and saw my weight distribution when sitting (33/66, front/rear) and in the attack position and it seems this is actually perfect. I am about 50/50 when in attack position and moving ever so slightly alters that reasonably well.
    Last edited by DaMaDo; 03-29-2014 at 05:48 PM.

  33. #33
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    I just attended a demo this morning at took out a medium. I'm 5'10" and did not feel cramped on it. The guy setting me up (5'11") rides a medium with a 60mm stem and wider than stock bar. The large was not available for me at. I'm currently riding a large Blur LTc with a 50mm stem and still feel a touch stretched out. I recently tried the Bronson in both medium and large and would need to go large. The Bronson felt like my BLTc but I think I like the Pivot better. I'll hit up the Sea Otter Classic and hopefully try the new Tracer carbon to see how that compares.

  34. #34
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    Quote Originally Posted by Southbay Bomber View Post
    I just attended a demo this morning at took out a medium. I'm 5'10" and did not feel cramped on it. The guy setting me up (5'11") rides a medium with a 60mm stem and wider than stock bar. The large was not available for me at. I'm currently riding a large Blur LTc with a 50mm stem and still feel a touch stretched out. I recently tried the Bronson in both medium and large and would need to go large. The Bronson felt like my BLTc but I think I like the Pivot better. I'll hit up the Sea Otter Classic and hopefully try the new Tracer carbon to see how that compares.
    The Bronson has a longer effective TT and reach than the same size M6. So if you need a large Bronson I don't see how you'd want a medium M6.
    Safe riding,

    Vik
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  35. #35
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    I don't know what to say other than it was a different set of trails this time. I didn't care for the feel of the Fox 34 last time but with the same pressure set this time around I thought it was fine.

  36. #36
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    I'd be really curious to try a medium M6 just to see the difference. I went out again in mine today and I love the feel of it. I feel I can make it do what I want and recover from almost anything. I never got that feeling in my medium Scott Spark. I know there's more than just size making a difference, but still.

  37. #37
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    Hey all. I am set on getting a Mach 6 and in the same boat as the OP on sizing, just up one. I am 6'1", 33" inseam, and 200lbs. My LBS has an XL demo that I took out over the weekend, and it was pretty damn awesome, but I'm thinking I might enjoy a L frame better, and they don't have a large for me to demo.

    When I first got the bike on the trail, it did feel a little big to me. My ride started out descending some steep technical rocky terrain, and I felt a little awkward at first (possibly because I am coming from a L Specialized SJ Evo 26"). Once I got to the climbing, the bike felt great, and after 30 min or so I was cleaning technical climbs that I had no chance at before. After an hour or so of climbing, it was fast technical rocky downhill and at this point i felt completely comfortable, and loved the performance of the bike. I was able to throw it around, and completely forgot about size. Actually I completely forgot about everything, until I hit the parking lot with a **** eating grin on my face.

    So point being, I am thinking that by switching to a Large, I may be sacrificing some climbing capability for an increase in maneuverability and "snappiness" on my descents, is that true? Or will I just be making myself more uncomfortable for no noticeable gain? Or will a large climb as well with all the advantages? Also, I like to run a 50mm or less stem, which the XL demo had. The XL was amazing, but if I am spending $6,000+ on a new build, I want to make sure I am getting the best fit possible.

    Anyone my size out there riding a Mach 6? What size? Any other thoughts or advice would be appreciated!

  38. #38
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    Quote Originally Posted by nlyso View Post
    Hey all. I am set on getting a Mach 6 and in the same boat as the OP on sizing, just up one. I am 6'1", 33" inseam, and 200lbs. My LBS has an XL demo that I took out over the weekend, and it was pretty damn awesome, but I'm thinking I might enjoy a L frame better, and they don't have a large for me to demo.

    When I first got the bike on the trail, it did feel a little big to me. My ride started out descending some steep technical rocky terrain, and I felt a little awkward at first. Once I got to the climbing, the bike felt great, and after 30 min or so I was cleaning technical climbs that I had no chance at before. After an hour or so of climbing, it was fast technical rocky downhill and at this point i felt completely comfortable, and loved the performance of the bike. I was able to throw it around, and completely forgot about size. Actually I completely forgot about everything, until I hit the parking lot with a **** eating grin on my face.

    So point being, I am thinking that by switching to a Large, I may be sacrificing some climbing capability for an increase in maneuverability and "snappiness" on my descents, is that true? Or will I just be making myself more uncomfortable for no noticeable gain? Or will a large climb as well with all the advantages? Also, I like to run a 50mm or less stem, which the XL demo had. The XL was amazing, but if I am spending $6,000+ on a new build, I want to make sure I am getting the best fit possible.

    Anyone my size out there riding a Mach 6? What size? Any other thoughts or advice would be appreciated!
    I'm 5'11" 33" pants inseam. Riding a L with a 65mm stem and 740mm bars. The bike fits well, but just. If I was any taller I would have to go for an XL.

    I started out with a 50mm stem, but had to swap in a 65mm stem to get a bit more room.

    I could ride an XL no problem, but would go for a 50mm stem.

    I ride tight twisty forest trails which is why I went L. If I lived in the desert I'd be riding an XL.

    You definitely give up on manoeuvrability as you increase wheel base.

    I don't see the shorter wheelbase as a detriment to climbing.

    Given that you want to run a 50mm stem I'd go with the XL - with of course all the usual YMMV cautions about fit advice from the internet.
    Safe riding,

    Vik
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  39. #39
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    yeah, you should be careful about sizing, sure. I am 6' even and 33" inseam and I'm on a large. It's super comfortable and just right for me. I wouldn't think the 1" taller would make for an XL size.
    I have too many bikes, but it's not enough

  40. #40
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    Quote Originally Posted by deerock View Post
    yeah, you should be careful about sizing, sure. I am 6' even and 33" inseam and I'm on a large. It's super comfortable and just right for me. I wouldn't think the 1" taller would make for an XL size.
    What size stem are you using?
    Safe riding,

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  41. #41
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    an 80 stem
    I have too many bikes, but it's not enough

  42. #42
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    Quote Originally Posted by deerock View Post
    an 80 stem
    That's important info. Nylso is taller than you and wants to use a stem that's 30mm shorter or even shorter than that.

    Every 25mm difference is like changing a frame size up or down.
    Safe riding,

    Vik
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  43. #43
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    What size Mach 6

    Quote Originally Posted by vikb View Post
    I'm 5'11" 33" pants inseam. Riding a L with a 65mm stem and 740mm bars. The bike fits well, but just. If I was any taller I would have to go for an XL.

    I started out with a 50mm stem, but had to swap in a 65mm stem to get a bit more room.

    I could ride an XL no problem, but would go for a 50mm stem.

    I ride tight twisty forest trails which is why I went L. If I lived in the desert I'd be riding an XL.

    You definitely give up on manoeuvrability as you increase wheel base.

    I don't see the shorter wheelbase as a detriment to climbing.

    Given that you want to run a 50mm stem I'd go with the XL - with of course all the usual YMMV cautions about fit advice from the internet.
    I am 5:10,5, I had a medium 5,7 with 65mm stem with 740 bars, it was borderline climbing steep technical climbs, I was concerned about slack seat post angle On M6.....I tested a large and it was a lot of bike, I also then managed to test a medium. I went for the medium and it was 100% the correct decision. I run the same 65mm stem and it climbs better than the 5,7. The set up is awesome.....don't go big if you don't have to, the longer TT sorts out the cramped feeling I had on the 5,7 and the slack seat post angle compliments the bike, as the higher you lift your seat the further the reach is between bars and seat without compromising climbing ability.....it all just works, what an awesome bike 100% happy.

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    Thanks for all the advice. Vic - I never really thought about stem lengths in that way, but it makes sense. I also see sa68's point about a slack SA, with seat all the way up for climbing. I've been stalking around the Pivot forums for a while, and read all the talk about the slack SA, but it never really clicked till just now! Thanks!

    I just found out the Pivot demo crew is going to be in town this Sunday, so I should get my chance to ride a large! I'll report back with my observations, and thoughts.

  45. #45
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    Quote Originally Posted by nlyso View Post
    Thanks for all the advice. Vic - I never really thought about stem lengths in that way, but it makes sense. I also see sa68's point about a slack SA, with seat all the way up for climbing. I've been stalking around the Pivot forums for a while, and read all the talk about the slack SA, but it never really clicked till just now! Thanks!

    I just found out the Pivot demo crew is going to be in town this Sunday, so I should get my chance to ride a large! I'll report back with my observations, and thoughts.
    A demo?...sweet that will answer a lot of questions - especially if they have a full size range for you to try out...

    Don't let the slack STA hypothesizing by folks who haven't spent a decent amount of time on the bike influence you. I'm climbing at a whole new level on the Mach 6 on techy terrain and the slack STA feels just great when pedalling the flats.

    Just a thought - if you want to try a short stem maybe bring one with you to the demo. I'm not sure what size is stock on the M6, but I want to say it's on the longer side.
    Safe riding,

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    Quote Originally Posted by vikb View Post
    A demo?...sweet that will answer a lot of questions - especially if they have a full size range for you to try out...

    Don't let the slack STA hypothesizing by folks who haven't spent a decent amount of time on the bike influence you. I'm climbing at a whole new level on the Mach 6 on techy terrain and the slack STA feels just great when pedalling the flats.

    Just a thought - if you want to try a short stem maybe bring one with you to the demo. I'm not sure what size is stock on the M6, but I want to say it's on the longer side.
    Great idea, pretty sure the stock build comes with an 80mm. I'll pull my 50mm off my current bike. Hopefully they'll be okay with that.

    I have no problems with the slack STA, and I agree with:
    Quote Originally Posted by miles e View Post
    The Mach 6 (like most Pivots) has a pretty slack seat tube angle, effectively decreasing reach for a given top tube length. I haven't heard the rationale for this from Pivot, but I suspect it is attributable at least in part to the inherent antisquat nature of the DW Link suspension.

    Designs like the Kona and Knolly will sink into their travel more when climbing, and a steep seat tube angle helps keep the riders weight from sliding too far back. The Pivot will ride higher in its travel, allowing the front to be more easily weighted under these circumstances.

    I happen to like Pivot's approach, as a) it allows for a shorter wheelbase (long reach/short stems are nice to a point, but eventually the wheelbase can become unwieldy) b) it allows for zero offset seat posts without putting the rider in a TT position at full extension.
    I see now that with a slack seat tube, you gain reach as the seat is raised for climbing. When the seat is all the way down, the cockpit may very well be too small for me, but who cares? If I have the seat all the way down, I am in downhill mode and don't sit at all anyways - if anything, it will get the seat more out of the way for me to get behind it when I need to be. Then with the touch of a button (modern dropper posts are amazing, and such an asset to enduro style riding) I pop the seat up, and not only put my legs in climbing position, but with the slack STA, increase reach and put my whole body back in a better seated riding position. At least I think that is the logic behind it, and it seems to make sense.

    Either way, I loved the XL, so if the L feels cramped, I am perfectly happy going with the XL. Just wanted to see if I can get a bit more out of a Large frame, and I am happy I get to give the Large a real demo ride now before deciding!

    Now... Next big decision... a 1x or 2x drive train... Hmmmm... Different thread.

  47. #47
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    Re: Mach 6 Frame size

    Quote Originally Posted by nlyso View Post
    Great idea, pretty sure the stock build comes with an 80mm. I'll pull my 50mm off my current bike. Hopefully they'll be okay with that.

    I have no problems with the slack STA, and I agree with:


    I see now that with a slack seat tube, you gain reach as the seat is raised for climbing. When the seat is all the way down, the cockpit may very well be too small for me, but who cares? If I have the seat all the way down, I am in downhill mode and don't sit at all anyways - if anything, it will get the seat more out of the way for me to get behind it when I need to be. Then with the touch of a button (modern dropper posts are amazing, and such an asset to enduro style riding) I pop the seat up, and not only put my legs in climbing position, but with the slack STA, increase reach and put my whole body back in a better seated riding position. At least I think that is the logic behind it, and it seems to make sense.

    Either way, I loved the XL, so if the L feels cramped, I am perfectly happy going with the XL. Just wanted to see if I can get a bit more out of a Large frame, and I am happy I get to give the Large a real demo ride now before deciding!

    Now... Next big decision... a 1x or 2x drive train... Hmmmm... Different thread.
    Reach doesn't change based on the saddle height. Reach is a constant measurement.
    Google reach and stack...

  48. #48
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    Quote Originally Posted by jazzanova View Post
    Reach doesn't change based on the saddle height. Reach is a constant measurement.
    Google reach and stack...
    You are right. What is the correct term for the distance from saddle position to head tube? Or is there one? I guess that's the measurement I have been mistakenly calling reach.

  49. #49
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    Going with the XL frame. It felt more comfortable and natural.

  50. #50
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    XL makes sense. The M6 is a little bit of new school (66 HA/16.9 CS) and a little bit of old school (short reach) and a whole lotta Rock and Roll!

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    Salespunk, I've noticed you on the Socal Forums. My wife and I are moving out to LA in a few weeks and I'd love some advice on where to ride, where not to ride, etc... Or someone to ride with once we get settled in. I've been checking out trail reviews, and socal forums, but nothing compares to someone who actually knows the area!

  52. #52
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    So I/m 5'10 and I rode the M6 (during a demo) , Medium with a 65mm stem and felt good.
    The large was not available.

    I currently ride a Blur LT medium with a 70mm stem and feels ok.

    Should I be good with the Medium M6? I'm 5'10

    thanks for the input.

  53. #53
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    Quote Originally Posted by Pedro Rios View Post
    So I/m 5'10 and I rode the M6 (during a demo) , Medium with a 65mm stem and felt good.
    The large was not available.

    I currently ride a Blur LT medium with a 70mm stem and feels ok.

    Should I be good with the Medium M6? I'm 5'10

    thanks for the input.
    I'm 5'10" as well (32" inseam) and honestly could have gone either way depending on what I was looking for.

    I demo'd a large at interbike and ended up getting a medium last week. The large felt just a little more stable but I had trouble moving around and behind the saddle. It seems like if you want a more all-around bike, go for the applicable size and if you want more of an enduro/super-d racer, you go up a size so it'll be more of a mini-DH bike like some of the other 6" 650b bikes.

    After putting 70 hard miles on it last weeek it didn't feel cramped at all, even though I put the 50mm stem and 740mm bars from my M5.7 on it.

  54. #54
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    I am 5'10" as well with a 30 inch inseam and demoed a large a couple of weeks ago. It felt really good but slightly less flickable than I had hoped. I am going to try a medium soon hopefully but I would certainly be happy with a large. The large was very stable at high speeds which was obviously nice.

  55. #55
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    Quote Originally Posted by Pedro Rios View Post
    So I/m 5'10 and I rode the M6 (during a demo) , Medium with a 65mm stem and felt good.
    The large was not available.

    I currently ride a Blur LT medium with a 70mm stem and feels ok.

    Should I be good with the Medium M6? I'm 5'10

    thanks for the input.
    You are in a good position because you could ride either size. If you are going with say a 50mm stem, then I would lean towards the large. I am also 5'10" and I think it fits me perfectly the 50. Also consider where you are going to run your seat. I am not a believer in the "KOPS" method of placing your seat. Keith Bontrager and others have debunked this having an effect on efficiency. However, the slack seat angle will make it harder to keep the front end weighted for a climb. You adjust to this pretty fast, but some don't like that aspect of the Mach 6. My seat is slid pretty far forward to compensate for this and since I have the large I had room to do so. I would have had to have the seat pretty far back on a medium.

  56. #56
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    I am also 5' 10" and could have gotten a large as I am also between the two sizes.

    My medium M6 came with the stock stem, which I think it is around 80mm. Looking down at the front hub, the handlebars are just behind it.

    Here in San Diego, you are often pedaling to the top of what you are about to go down, so from that perspective, having the stock stem I think offers a little more control over the fork for the ups, and certainly offers enough confidence for the downs because of the head tube angle and the longer travel, so the medium is fine. By comparison, I would say my M6 with the 80 mm stem feels about 1/3 lighter on the front end than my M429C with a 70mm stem (again because of head tube angle and more travel).

    If you are doing more DH stuff, a shorter stem will put your weight even further behind the fork which I would imagine would start to get annoying if you do a lot of climbing. If I was more of a park rider, I think I would have gone with the large and a shorter stem.

    Having the medium M6 allows me to use the bike in more of an XC setting where I need it, but also allows me to use the bike in a more downhill'ish mode if I need that also.

  57. #57
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    Mach 6 Frame size

    Wouldn't an extra 30 mm of top tube keep the front end weighted as much as 30 extra mm of stem? I would think so, but not 100% sure. The axis is the rear wheel, which is why a half an inch of chainstay length changes handling so much. I will take the easy manualling of short chain stays any day.

    I also have the option of running the seat further forward on the seatpost with the large, which will definitely aid in climbing.

    Most of the reviewers didn't like the long stock stem, but it's all a matter of preference.

  58. #58
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    People need to stop worrying about the seat tube angle. It's actually steeper than a M5.7 and even the 429, and nobody complained about them.

    What's happened is that most of the other 6" bikes have steep angles because their suspension squats under power while the DW-link extends. They have to have steep seat tubes, Pivots don't...that's why all Pivots have slack seat tube angles.

  59. #59
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    Mach 6 Frame size

    It may be fine at average height, but I can see it would be an issue for someone running a very long seatpost. Because of the virtual seat tube angle, you could have a much slacker angle than what it's designed for.

  60. #60
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    Quote Originally Posted by tadmcmichael View Post
    It may be fine at average height, but I can see it would be an issue for someone running a very long seatpost. Because of the virtual seat tube angle, you could have a much slacker angle than what it's designed for.
    The virtual ST angle is based on whatever they consider the average seat post extension for the applicable height for the frame...or somewhere around where people who buy the recommended size have theirs. Nobody is talking about going down a size, only up if you want a longer top tube.

    This is neither a Mach 6 or a Pivot "problem." They all have slack seat tubes and nobody spoke a word about it until someone reviewing the M6 looked at the website or brochure and said, "Hey, this is slack." They didn't say it didn't fit, put their weight too far back, couldn't climb, nothing. Now everybody acts like it'll flip over if you even look at a hill. The M6 was voted the most versatile in the MTBR trail bike review, FFS.

    I have a 50mm stem on my medium and it climbs steep sections just fine. It doesn't take much effort to get the front wheel up and over an obstacle, but it doesn't take any to keep it on the ground either.

  61. #61
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    Mach 6 Frame size

    Quote Originally Posted by SDMTB'er View Post
    I am also 5' 10" and could have gotten a large as I am also between the two sizes.

    My medium M6 came with the stock stem, which I think it is around 80mm. Looking down at the front hub, the handlebars are just behind it.

    Here in San Diego, you are often pedaling to the top of what you are about to go down, so from that perspective, having the stock stem I think offers a little more control over the fork for the ups, and certainly offers enough confidence for the downs because of the head tube angle and the longer travel, so the medium is fine. By comparison, I would say my M6 with the 80 mm stem feels about 1/3 lighter on the front end than my M429C with a 70mm stem (again because of head tube angle and more travel).

    If you are doing more DH stuff, a shorter stem will put your weight even further behind the fork which I would imagine would start to get annoying if you do a lot of climbing. If I was more of a park rider, I think I would have gone with the large and a shorter stem.

    Having the medium M6 allows me to use the bike in more of an XC setting where I need it, but also allows me to use the bike in a more downhill'ish mode if I need that also.
    The above captures my thoughts/feelings on my Mach 6 vs my Tallboy as well. I'm just up the I15 freeway from him (Temecula), so I'm sure we ride similar type terrain.

    I'm 6'-0" and ride a Large Mach 6 with 70mm stem and 760mm bars. On my Large Tallboy I run a 80mm stem and 750mm bars. I feel both fit me perfectly.

  62. #62
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    For your reference, my height 168cm and ride on Medium M6 with RF Atlas 35mm stem. Enjoying the ride and love it.

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    Looking for more info on this, hoping to get a few more "medium vs large" inputs. I'm 5'11" with a 32 inseam. Borderline on which size to get as I'll be running 35mm stem and 780mm bars. Right now I have my order placed for a large but have until Sunday night to change it before it starts getting built. Also will be going with a fox 36 @ 160mm instead of a 150mm fork.

    Coming off a yeti sb66 in a medium that was run with a 50mm stem and 740mm bars. That felt right at the edge of comfortable. Riding is trail with aggressive descents and the occasional 10-12 foot gap jump.

  64. #64
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    Large makes more sename than medium based on your size.
    Safe riding,

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    Idaho, I am 5'10" with a 30" pant leg inseam. I was on the fence between a large and medium and could have gone either way but ended up going with a medium with an 80 stem. The large felt very good and I certainly could have ridden it but the medium was more flickable and better for riding tight single track around my area. The large with a 35 sounds pretty much perfect for you. You are going to be very stoked on the M6. Stick with your large order.

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    At 5'10" with a 50 mm stem, I love my large. Based on the stem you want to run, you are firmly in large territory.

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    Thanks for the input. I will stick with the large I had intended on ordering and get it posted up in the Mach 6 build thread once it's done. Now just tossing around wheel ideas as there are an incredible amount of options!

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    I'm 5'10 with a 32 inseam, and demo a medium with a 65stem, a bit to small for me.

    I ended up ordering a large which I am currently building iwith 750bars 50mm stem and a 160mm pike.

    Just waiting for my wheels in order to ride it.

  69. #69
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    I agree with tadmcmichael. 5'11" running a large with a 50mm stem for about a year. Your 35mm stem on a medium would be far too small unless you were coming straight over from BMX with a strong lil bike preference.

  70. #70
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    Quote Originally Posted by Idaho View Post
    Looking for more info on this, hoping to get a few more "medium vs large" inputs. I'm 5'11" with a 32 inseam. Borderline on which size to get as I'll be running 35mm stem and 780mm bars. Right now I have my order placed for a large but have until Sunday night to change it before it starts getting built. Also will be going with a fox 36 @ 160mm instead of a 150mm fork.

    Coming off a yeti sb66 in a medium that was run with a 50mm stem and 740mm bars. That felt right at the edge of comfortable. Riding is trail with aggressive descents and the occasional 10-12 foot gap jump.
    I'm 5'11, ride aggressively downhill, and there are a lot of steep technical climbs in my area. I was on a Yeti SB66c Medium with a 35mm stem and had 711mm bars. I had a 65mm stem on the SB and it felt too long for sure. 50mm probably would have been my max on a medium. I am now on a Medium Mach 6 with a 50mm stem and 760mm bars.

    I prefer more nimble bikes that are easy to jump and good in technical terrain over super long and slightly more stable rides so that almost always puts me on a medium frame. Over the SB66, I found the seat tube on the Mach 6 to be quite slack and it was hurting my back on the steep climbs we have. I didn't have this problem on the SB66. I switched quickly over to a 160mm Pike with travel adjust and that helped a lot, though I still feel it's an issue for me. I slid the seat quite far forward on the rails which helps as well. I think that's the main thing with guys 5'11 going to a medium - you are pretty far over the back wheel when your seat is at full height. The top of my saddle is 12.25" out of the seat tube at full height with clipless pedals. I have room to lower my KS LEV 150 post 2.5".

    If you are 5'11 and adamant about using a 35mm stem, I would say you should probably go with a large. A 35mm on my medium would be a touch too short and this is coming from someone who prefers a shorter cockpit.
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  71. #71
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    Quote Originally Posted by NOBLwheels View Post
    I'm 5'11, ride aggressively downhill, and there are a lot of steep technical climbs in my area. I was on a Yeti SB66c Medium with a 35mm stem and had 711mm bars. I had a 65mm stem on the SB and it felt too long for sure. 50mm probably would have been my max on a medium. I am now on a Medium Mach 6 with a 50mm stem and 760mm bars.
    If you subscribe to the formula of 2/1 bar width increase/stem length decrease, a 35mm would be close enough with 780mm bars.

    I'm an inch shorter and use 750mm bars with a 50mm stem on a medium. No problems climbing and it seems to really rail corners with the rearward bias that an attack position gives. The hub is way forward of the bars when looking down, but it works. Best of all is that I don't have to have the saddle lowered to get behind it (and not get hung up in that position), like I did on a large.

  72. #72
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    Seems to be a few conflicting reports but I settled on the large ultimately. Hope it works out as that's also what Pivot suggested when I called them. The said on this bike people will generally up-size where as they will generally down-size on their new XC bikes.

    Ended up with Chromag BZA bars at 780mm and a 40mm Haven stem as the 35mm Atlas from Race Face was out of stock.

  73. #73
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    I believe you'll end up pretty happy with your build Idaho. I have the same height and inseam measures and built my Mach 6 with a size large frame, 780 mm wide bars and a 50 mm stem. It feels great! Very playful and easy to throw around

  74. #74
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    Hi, I found a very good deal for a new small mach 6 frame, however I am 5' 10"
    I Demoed it, at first I felt it small as expected. then after a few adjustements of the seat and a wider handlebar I felt it better. Almost as my currently medium bike.

    unfortunately I cannot demo a M or L frame. so my question is if a size smaller than the recommended would be fine?. I want it for AM.
    In the geometry charts there is only 0.57 inches of difference in the top tube lenght.

  75. #75
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    Quote Originally Posted by albxor View Post
    Hi, I found a very good deal for a new small mach 6 frame, however I am 5' 10"
    I Demoed it, at first I felt it small as expected. then after a few adjustements of the seat and a wider handlebar I felt it better. Almost as my currently medium bike.

    unfortunately I cannot demo a M or L frame. so my question is if a size smaller than the recommended would be fine?. I want it for AM.
    In the geometry charts there is only 0.57 inches of difference in the top tube lenght.
    Wow 5' 10" on a small?? My GF is 5'6" and she could easily be on a medium...she rides a small with a 60-75mm stem.

    I'm 5'11" and ride a large with 65mm stem and could easily ride a XL. No way I could ride a medium unless I went with a 90-100mm stem which isn't a setup I'd want.

    FWIW - we ride techy tight AM forest trails in BC.

    Having said all that there is more to bike fit than height so if you felt okay on the small that's more important than 1000 internet opinions on bike fit.

    What size stem was on the bike you tried? If it was short at least you can put a larger stem on it. If it was a longer stem you won't have any way to extend the reach since you already tried some wider bars.
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  76. #76
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    The stem was 70mm longer, I can order the Medium but it would be a little more expensive. Since the small is already in my country (Mexico) and the medium have to be import it.

  77. #77
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    I'm 5'10 and just bought a Large with a 55mm stem.
    I did demo the medium and felt small for me.

    I think you should be at least on a Medium, small no way.

    The guys from the bike shop should be able to tell you that the bike it's to small to small for you, if not then their are just trying to sell the bike no matter what.

  78. #78
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    Pedro you are right.

    I will order the large frame like you, since I want to use a short stem.

    Thank you.

  79. #79
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    I'd say it's risky for the long term personally, but if u feel ok while demo-ing the small and it feels OK, then fine, especially since it's such a deal. Personally I wouldn't do that as you always 'grow into the bike' after a few months and I know I would regret a decision like this. I'm 5'11 and I ride a Large and after changing stem, etc. it fit me like a glove. I'm a pretty techy rider too...and good luck!
    I have too many bikes, but it's not enough

  80. #80
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    Mach 6 Frame size

    Quote Originally Posted by albxor View Post
    Hi, I found a very good deal for a new small mach 6 frame, however I am 5' 10"
    I Demoed it, at first I felt it small as expected. then after a few adjustements of the seat and a wider handlebar I felt it better. Almost as my currently medium bike.

    unfortunately I cannot demo a M or L frame. so my question is if a size smaller than the recommended would be fine?. I want it for AM.
    In the geometry charts there is only 0.57 inches of difference in the top tube lenght.
    I would wait - a ride that is a few hours is different than a demo. You want a bike that is big enough to make adjustments without going to extremes. Your height is right in the middle for a medium or a large. I got the medium and I am also 5 10 with a 33 inch inseam and the bike fits me perfectly. Using the stock stem at 65mm and stock bars at 740mm.

  81. #81
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    Wow, at 5'10" there is no way I'd go with less than a medium. At 5'11" with a 35mm stem, my large feels like it should have been with a 50mm. I would have been proper screwed had I got a medium in my opinion. That is with 800mm bars as well.

  82. #82
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    Agree! At 5'11, longish arms and legs, I'm on a large with a 50mm stem and 780mm bars and it feels spot on. A medium sized frame would feel a little cramped with this set up for sure. A small for a 5'10 I doubt that would work for the long haul...

  83. #83
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    At the end I ordered a large frame.

    Thank you all of you for the answers.

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    Here is me at 5 10, 33 inch inseam on a medium M6. The bike feels perfect for me.

    Mach 6 Frame size-screen-shot-2015-01-24-4.41.30-pm.jpg

  85. #85
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    What size stem you running? I just ordered a mach 4c 27.5 in size large with a 70mm stem and I'm 5'10". I live in Texas with all types of riding, just no downhill. The new mach 4 has a slightly longer top tube. Did I make a mistake on Size? I can change my order, but need to do so asap!!! I'm currently on a large Tallboy.


    Quote Originally Posted by SDMTB'er View Post
    Here is me at 5 10, 33 inch inseam on a medium M6. The bike feels perfect for me.

    Click image for larger version. 

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  86. #86
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    Mach 6 Frame size

    Quote Originally Posted by kumquat View Post
    What size stem you running? I just ordered a mach 4c 27.5 in size large with a 70mm stem and I'm 5'10". I live in Texas with all types of riding, just no downhill. The new mach 4 has a slightly longer top tube. Did I make a mistake on Size? I can change my order, but need to do so asap!!! I'm currently on a large Tallboy.
    80mm (stock stem).

    I would have gotten a large if I picked up a Mach 4 as they run on the small size. I think you will be fine.

  87. #87
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    you should be good, I have a Mach 6 with a 55 stem but I do a lot of DH, It fits perfect.

    You should be good with L and a 70mm stem

  88. #88
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    Mach 6 Frame size

    Quote Originally Posted by SDMTB'er View Post
    80mm (stock stem).

    I would have gotten a large if I picked up a Mach 4 as they run on the small size. I think you will be fine.
    No, the M4 is 6/10" longer.

  89. #89
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    Quote Originally Posted by tadmcmichael View Post
    No, the M4 is 6/10" longer.
    Yes, this is correct, the m4 is longer.. I actually think the gentlemen above looks a little big on the bike so I'm going to stick with the large. Especially since im in flat texas. 5 10 sucks for sizing

  90. #90
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    Mach 6 Frame size

    I look at it the other way, you can't make a mistake. Since I am 5'10" I could ride a medium or large and be comfortable. Just went the large route because I like to ride a 50mm stem.

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    It also depends on what trails you ride....I ride a m6 medium and am 5 10, it is great on the bigger open trails but my old 5,7 was better on the tighter single track, I am so glad I didn't go with the large as I would have really struggled on the tighter local trails....

  92. #92
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    Mach 6 Frame size

    Quote Originally Posted by kumquat View Post
    Yes, this is correct, the m4 is longer.. I actually think the gentlemen above looks a little big on the bike so I'm going to stick with the large. Especially since im in flat texas. 5 10 sucks for sizing
    I tried the large and it felt too rangy. The more you have to reach forward, at least for me, it makes it harder to get to the back of the bike in the gnar.

  93. #93
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    Mach 6 Frame size

    Quote Originally Posted by sa68 View Post
    It also depends on what trails you ride....I ride a m6 medium and am 5 10, it is great on the bigger open trails but my old 5,7 was better on the tighter single track, I am so glad I didn't go with the large as I would have really struggled on the tighter local trails....
    I tried the large and it felt too rangy for me.

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    Mach 6 Frame size

    Quote Originally Posted by SDMTB'er View Post
    I tried the large and it felt too rangy for me.
    With the stock stem, yes. It's a longer reach to the bars with your Medium and 80mm stem than my Large with the 50mm.

  95. #95
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    Mach 6 Frame size

    Quote Originally Posted by tadmcmichael View Post
    With the stock stem, yes. It's a longer reach to the bars with your Medium and 80mm stem than my Large with the 50mm.
    Actually I believe Pivot is no longer selling the FSA 80mm stem as standard. The bike I tried had a shorter stem and different brand. Maybe in the 50-60mm range. I think if you are trying to setup a M6 as a mini DH bike, short stem is the way to go. But if you are more of an all around trail rider involving steep climbs as well as technical downhills the 80mm stem seems to be a good compromise. For me it also allows me to get a fairly close feel to my Mach 429 cockpit. I have my seat height and effective top tubes set exactly the same with 80mm stems on both bikes.

  96. #96
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    They aren't selling the M6 with a 80mm stem after websites (Pinkbike, Vital, Enduro, etc.) and the mags popped off about how bikes targeted at the AM/Enduro segment need short stems, wide bars, and a dropper.

    No doubt the setup works well for SDMTB'er and he's pleased with it. I personally wouldn't want to set up my M6 like I would a 100mm endurance-oriented 29er. In my eyes, that medium looks really quite small, especially given how short the M6 wheelbase is to begin with. I'd find it really hard to get my chest down, elbows out, and weight centered on that medium if I were 5'10. But again, it's not my M6.

    I'm on a large with a 50mm stem, stand at 5'11", and just want to add that these bikes with longer front centers may not feel like the bike you've loved for 5 years. I feel like the evolution in geometry may take a bit of time to adjust to but there's a reason people are moving that direction. Pivot's flavor or "long and slack" sits decidedly in the middle of the spectrum with Mondraker way the hell out there in another County, Kona a ways out, and Santa Cruz/Devinci/Others less so.

    I've been railing mine for over a year and am extremely pleased that I went with the M6.

  97. #97
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    I'm 5'10" w/31" inseam on a medium Mach 6. I love the way the bike feels and rides. My previous bike was a large and I tried the big frame/short stem thing. It was my first FS bike, coming from a bike that was a touch too small and I wanted to feel like I was in the bike blah blah blah...long story short I love the feel of the medium size frame and wouldn't have it any other way.

  98. #98
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    Mach 6 Frame size

    Quote Originally Posted by OriginalDonk View Post
    They aren't selling the M6 with a 80mm stem after websites (Pinkbike, Vital, Enduro, etc.) and the mags popped off about how bikes targeted at the AM/Enduro segment need short stems, wide bars, and a dropper.

    No doubt the setup works well for SDMTB'er and he's pleased with it. I personally wouldn't want to set up my M6 like I would a 100mm endurance-oriented 29er. In my eyes, that medium looks really quite small, especially given how short the M6 wheelbase is to begin with. I'd find it really hard to get my chest down, elbows out, and weight centered on that medium if I were 5'10. But again, it's not my M6.

    I'm on a large with a 50mm stem, stand at 5'11", and just want to add that these bikes with longer front centers may not feel like the bike you've loved for 5 years. I feel like the evolution in geometry may take a bit of time to adjust to but there's a reason people are moving that direction. Pivot's flavor or "long and slack" sits decidedly in the middle of the spectrum with Mondraker way the hell out there in another County, Kona a ways out, and Santa Cruz/Devinci/Others less so.

    I've been railing mine for over a year and am extremely pleased that I went with the M6.
    Just curious - say you had to actually XC the M6 around 20 plus miles per ride and roughly a third of that ride was steep and technical downhills, a third was average 10 percent climbing at times peeking into the mid 20s, and the other third was flat. And let's also say that you have taken lots of time to dial in your bike fit that when off by just a hair causes discomfort in the usual areas (wrists, lower back, etc). Wouldn't you want to approximate a similar fit as your XC rig that you knew helped you maintain your riding comfort for hours in all sorts of terrain? That is my mindset. That being said, the rest of the M6 geometry with the slack seat angle, the longer travel, and the smaller wheels is what makes this bike own the DH stuff.

    For example here in San Diego you will climb at least, LEAST, 1500 feet to have any sort of fun on the DH. Having a super long, slack bike with a floppy front end due to the shorter stem would get very annoying within the first 20 feet of your first 20 percent grade climb. So I am not really about chasing a mythical reach metric because VitalMtb says it is so, than fitting the bike to my specific use case and body dimensions. The reach measurement as far as I know is entirely subjective as far as what is "right." But there is a fair amount of work around proper bike fit based on knee angle, extension, position relative to pedals, etc.

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    I can be considered as a small built person at 5' 7" andI went with a size M on the Mach 6. Using a 50mm stem & 750mm handlebar. It fits me well. I didn't feel uncomfortable when riding it up or down. I guess if the sizing wasn't too far off (like, in my case, going for an XL or an L size), your body will eventually adapt to the new riding position. Just my own opinion. I don't ride super extreme downhill stuff. Just regular all mountain terrain which involves a fair amount of climbing as well as descending.

  100. #100
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    I decided to do a bike fit via competitive cyclist and my results came back with the below.. Results indicate I should be on a Medium Pivot. Are these on-line fit calculators pretty legit? They required a lot of measurements.

    Standover - 20.4 - 31.1 inches

    Top Tube - 23 - 23.4 inches

    Stem Length - 9.6 - 11.2 cm

    BB Saddle Position - 70.1 - 71.6 cm

    Saddle to Handlebar - 53 - 54.6 cm

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