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  1. #1
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    Softening up a harsh ride

    I have a Trex FX 7.2, 700c Hybrid. It's an aluminum frame w/ small high pressure tires. The ride is plain old uncomfortable. I am trying to render it pleasant to ride, so that it ceases to collect dust and can be reintroduced to the road. My thought is the only hope I have of easing the ride is pneumatic shock absorption. I need more wheel.

    My estimation is a 27-30mm width rim, a 35-45mm tire and tubeless is my best bet to get more volume, lower pressure, and better ride. Has anyone ever tried something like this? Is it likely to turn out wasted money on a wasted effort?


    Thanks for your time and thoughts.

  2. #2
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    According to the specs it has 700-35s. Yes yours is an aluminum frame, my bike is steel but a semi sports not touring geometry with hard riding deep Vee rims. I found 32 mm at 70-75 in the front and 80-85 in the rear is pretty decent. I am currently riding 28's at 85 and 95 pounds. A bit less comfy. 700-35's on the errand bike at 55-60 pounds in the front and 60-70 in the rear. If you don't have too many potholes for pinch flats, have you tried lower than maximum tire pressures?

    Tire Sizing Systems

    Scroll down most of the way to the color chart with green squares. It is conservative. You can fir at least a size larger tire with little risk than what is indicated. So you might be able to try a 45 mm on your current rims.

    CB can address tubeless.

    BrianMc

  3. #3
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    Rim width won't make much of a difference, and a 27-30mm rim is extremely wide. Not even sure they made them that wide, and if they do, they will be 29er downhill or freeride wheels. I would stick with the wheels you have. You need to find out the widest tire you can fit on your frame. Going to a larger tire with lower pressure will make a big difference, tubeless can also help quite a bit. I would be willing to bet you can't go too much wider than what you have now, maybe 42 or 45mm, but I could be wrong. If you can't find your answer on the web, go to a bike shop that stocks some different size tires and see if they can try out a couple for you.

    One thing to keep in mind, when you run road tires tubeless, you generally want both UST/tubeless ready wheels and tires because of the higher pressure. Not AS big of a deal if you're going with wider tires, but still a good idea.

  4. #4
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    What size/pressure tires, and is the rough ride a problem at the seat or at the handlebars (or both)?

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    Softening up a harsh ride

    A better fork may make some improvements if you get a lot of high frequency vibration at the handlebars. Agree to avoid the super wide mtb rims. Not worth it. With tires in the width range we're discussing here, increases in volume will be marginal.

    Tire pressure will be a big component.

    Depending on where your discomfort is, you might also consider finding a new saddle, new grips, and/or a new fork.

  6. #6
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    Thanks for all the responses guys.

    The ride is uncomfortable front to back. The bike came with a steel fork that is less substantial than the fork on my Fargo. I can't imagine doing better than that w/o forking out the dough on ti or carbon (not gonna happen.)

    I can steal the Selle Anatomica and Thudbuster off my Fargo and give that a try (once I have cranks back on this sucker.) Grip wise it came with some quite soft rubber grips, other than hating them entirely they never really sorted out enough of the jostle.

    Is it even worth trying tubeless w/o a change of rims? Just running lower pressure is not something I am willing to try, too many snakebites on these tires. Looks like a trip to the LBS is in order for tires. It's strangely hard for me to find tires/rims simply by typing specs like size and width into search engines.


    Again, thank you for the outpouring of wisdom and help.

  7. #7
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    Softening up a harsh ride

    Quote Originally Posted by Jumpmonkey View Post
    Thanks for all the responses guys.

    The ride is uncomfortable front to back. The bike came with a steel fork that is less substantial than the fork on my Fargo. I can't imagine doing better than that w/o forking out the dough on ti or carbon (not gonna happen.)

    I can steal the Selle Anatomica and Thudbuster off my Fargo and give that a try (once I have cranks back on this sucker.) Grip wise it came with some quite soft rubber grips, other than hating them entirely they never really sorted out enough of the jostle.

    Is it even worth trying tubeless w/o a change of rims? Just running lower pressure is not something I am willing to try, too many snakebites on these tires. Looks like a trip to the LBS is in order for tires. It's strangely hard for me to find tires/rims simply by typing specs like size and width into search engines.


    Again, thank you for the outpouring of wisdom and help.
    Fit the widest tires your bike can handle and use lower inflation pressure. The cush will not change if you do not change the pressure, no matter the tire size, though a tire with a more supple casing will have a smoother ride.
    The stock Hardcase Lite tires are heavy and stiff. Not good for ride quality.

    No need to go tubeless. If you are pinch flatting now, you may just start pinch flatting the casing (destroying the tire) instead of the tube.
    The current rim width is fine. Too wide a rim makes the ride harsh, no matter the pressure.
    mtbtires.com
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  8. #8
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    I'd bet you could find a used hybrid type carbon fork on the 'bay or at a bike co-op for a fairly reasonable price. It's not a high end carbon fork by any means. You could also look for a higher quality steel fork. Not all steel forks are created equally. Differences there will be a little less dramatic, though, so it'd probably be the last change I make in relation to the other suggestions in this thread.

  9. #9
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    Thanks for the further clarification. I'm going to scrap this project before I put money into it. I'm not convinced I can get enough smooth and enough reliability out of the 700c's. I'd be better off selling the frame for a few bucks and putting it toward a light alu 29er frame. I'm confident in Big Apples. I have yet to flat one over many miles in the same terrain and they offer plenty cush.


    Thanks again, you guys have been tremendously helpful!

  10. #10
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    Softening up a harsh ride

    Quote Originally Posted by Jumpmonkey View Post
    Thanks for the further clarification. I'm going to scrap this project before I put money into it. I'm not convinced I can get enough smooth and enough reliability out of the 700c's. I'd be better off selling the frame for a few bucks and putting it toward a light alu 29er frame. I'm confident in Big Apples. I have yet to flat one over many miles in the same terrain and they offer plenty cush.


    Thanks again, you guys have been tremendously helpful!
    A 29er uses 700c wheels and tires, too.
    mtbtires.com
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  11. #11
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    Shiggy,

    I'm aware of that. I have a slightly wider wheel from my old SE Stout 29er sitting in the rear of the Trek frame right now with the 35mm tire fitted. I did it because it took about 10min and cost me absolutely free to try. The result, as ya'll had stated earlier, was not worth mentioning.

    Thanks

  12. #12
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    So what tires are you running and at what pressure? Rider weight? My 700x 35 panaracer paselas are great on my crosscheck. 55 psi front and 60 rear, rider at 235 lbs.

  13. #13
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    leeboh,

    I've decided I'm going to leave it be for now. I run about 90psi, and at that the bike has huge issues with pinch-flats. Lowering the weight on the current tires is just not a viable possibility. Having run down what, to me, was the one possible saving grace for the frame, I'm going to hork it for a few bucks. Thanks much though!

  14. #14
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    Been looking at big apples to commutify my Karate Monkey. Maybe a spring project.

  15. #15
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    Wow, no wonder if the ride is harsh if you have 90 psi in 35c tires! How much is the weight of rider + gear?

    Try lowering the pressure and using more supple tires. Probably no need to even change tire size. These changes really make a huge difference. I have 28c tires that provide a smoother ride than my 35c winter tires at any pressure!

  16. #16
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    Quote Originally Posted by Jumpmonkey View Post
    leeboh,

    I've decided I'm going to leave it be for now. I run about 90psi, and at that the bike has huge issues with pinch-flats. Lowering the weight on the current tires is just not a viable possibility. Having run down what, to me, was the one possible saving grace for the frame, I'm going to hork it for a few bucks. Thanks much though!
    Pinch flats at 90psi on 700x35's? Something is not right with that....there is necessary information missing. I run around 65psi in 700x32's (total weight just shy of 200lbs) and haven't had a single flat in several hundred miles.

  17. #17
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    I'm curious if you have a pump or a gauge or if you are just guessing at the pressure. Or are you 400lbs? Even at my 260lbs, 90psi on 35's shouldn't be pinch flatting. Heck I don't think I'd run quite that high even.

    A recent Big Apple convert here too, I went 2.35" but you have to have the frame clearance for whatever you pick. The ride comfort is pretty amazing and I was shocked to find they roll at least, if not more, fast than my 40mm Mondials did. I'm running 40psi rear and 30 front and it works really nicely for mostly pavement and hard pack surfaces.

    You could also look at the Kojaks and a few others, maybe the Baby Big Ben.

  18. #18
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    definately missing something here. What sort of terrain are you riding? This bike and tire combo really isn't the best for aggressive rocky trail riding with drops, which it sounds like you're doing.

    I have a bike similar to this, 700c hybrid that came with 40mm (1.5") wide tires (Kenda Happy Medium). Huge diffeence when I went from these to 1.9" tires (Kenda Karma). Dropped the pressure from 45 to 32 psi and it has plenty of cushion. Would have gone to a larger tire, but the rim width (17mm) and frame clearance limited my tire choice. Before, i wouldn't want to tank it off road at all, but now it's pretty good with the rocks & roots. Not a single pinchflat, and I weight 240lbs.

  19. #19
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    King,

    I'm a light guy 150 soaking wet. Ninety-psi on a tire gauge. Yes, I have had continual pinch flats on these things. Why have I had continual pinch flats? I know once I plain old slammed into a curb instead of going over/onto the curb, aside from that they just seem prone to it. I'm aware you need proper clearance for any tire. I'm running a 2.35" Big Apple w/ MTX 33 on the rear of my Fargo and a 2.0" on the front, so I'm quite familiar with them. I was hoping to get an unused frame back on the road. After asking around here a bit, I lack confidence in the viability of the project, so, I'm going to get rid of it. All the help is truly appreciated.

  20. #20
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    Watt,

    I don't do MTB (Ironically, considering the forum.) The cruel and harsh life that my trek endured involved going up and down hilly road between my house and town, and getting me to my various errands in town. The worst it endured was cutting through a disused gas station parking lot. It was used almost exclusively on the road. Its off-road life was over walk/bike/horse trails and the occasional bit of lawn. I'm not enough of a numpty to have driven it through pot-holes, sewer-grates and the like. As mentioned in the above post, the one exception was when I botched a curb mount and slammed my tire. Thankfully I realized I'd flatted it as I walked into the bike shop (good timing.) Thanks.

  21. #21
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    What tire gauge are you using? I have encountered more than a few that are completely bass-ackwards in accuracy. I have more confidence in the gauges on my floor pump and on the inflater for my compressor, though the compressor and the inflater are a few psi different. Still, it's only a few psi. I have seen some digital gauges that are tens of psi off from each other.

    The way you ride does play a role, too. Can't go smashing into curbs and obstacles on skinny tires. If you ride that stuff, you need finesse.

  22. #22
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    Nate,

    Using the Tire gauge I've been using for the car for ages (standard vehicular tire gauge, and yes, it is rated to gauge higher pressures I had checked that.) Never went in for the digital stuff. I don't smash into things, aside from when I fail/crash, and I don't count that against the tires when I do. That's all down to the idiot driving it into the obstacles. Thanks.

  23. #23
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    Ya, my ride is fine running an old all steel mountain bike with Kenda Kwest tires, max pressure of 65psi, and I am solidly a clyde. I am not sure if I have the 26 x 1.25 or was only able to find the 26 x 1.5. Never had any kind of flat (I did slime them, though, since I am in a desert and goatheads appear out of nowhere...), road feels super smooth, probably hundreds of miles by now since I have been commuting on those tires since... January, I think. The cobblestones at work are annoying though!

  24. #24
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    It sounds like it's not riding style (with the exception of the curb hopping incident) that's causing pinch flats, so I wonder what else could be the cause. Have you taken the tires and rimstrip off to make sure there's nothing inside? Sometimes, the original manufacturing line leaves sharp bits and pieces in the wheel; because they're lazy. You shouldn't be getting pinchflats at this pressure if you weigh 150lbs.

    If everything else on the bike works OK and it's just the ride quality, I'd do the following:
    1. Lower the PSI to 45 and ride it for a litle while. With a 35mm tire, you should be able to roll at 45 psi without too much lost energy to resistance.
    2. If the above feels good, try 50 psig. Running a 35mm tire at over 50psi for casual road use isn't necessary unless you just want the speed.
    3. If it still feels hard and you have frame clearance, get some 2" 29er tires and run them at 35 psig. I'm sure there's better out there, but the following are cheap, and if you get something similar on a free shipping day, worth it.
    Hutchinson Python 29-in Mountain Tire - Bicycle Tires

  25. #25
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    Quote Originally Posted by Jumpmonkey View Post
    Nate,

    Using the Tire gauge I've been using for the car for ages (standard vehicular tire gauge, and yes, it is rated to gauge higher pressures I had checked that.) Never went in for the digital stuff. I don't smash into things, aside from when I fail/crash, and I don't count that against the tires when I do. That's all down to the idiot driving it into the obstacles. Thanks.
    Do you have ANY other kind of gauge to compare to? I'd be suspect of the gauge unless demonstrated that it's consistently within a couple psi of other gauges at the pressures you're using on the bike. Based on the discussion so far, it's the most likely culprit in my mind.

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    No, I have no others to compare it to. I used to have one on my Park floor pump, but word on those was they were considered to be unreliable. It varied widely from my tire gauge and given its reputation, the Park was disregarded and the tire gauge was given preference.

  27. #27
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    Quote Originally Posted by Jumpmonkey View Post
    No, I have no others to compare it to. I used to have one on my Park floor pump, but word on those was they were considered to be unreliable. It varied widely from my tire gauge and given its reputation, the Park was disregarded and the tire gauge was given preference.

    Maybe take your gauge to a shop and compare with one of theirs. It's what I have done with suspect gauges in the past. Compare with what the mechs use and trust, not with whatever is on the sales floor (unless the shop sells the exact model that the mechs use).

  28. #28
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    Nate,

    Thanks much, I'll have to check that out next time I get by the LBS!

  29. #29
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    Is it possible you're leaving the tube slightly pinched between the tire and rim when you put a new tube in? Or maybe pinching it with the tire lever? It's a lot harder to get a tube in a narrow road tire than a mountain bike tire. 90psi in a 35mm tire is crazy. I run 60psi in 32mm tires and I weight a bit more than you plus a relatively heavy backpack. You should be able to swing as low as 50psi. Getting a new bike is overkill. If all else fails, get new tires and/or go tubeless and run lower pressure.

  30. #30
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    I used to run 90 PSI in my 32c tires, and then I heard of the 15% rule (Google it) and dropped to ~60 in my front. Rides considerably softer. I still run the rear at about 90, but my total weight is about 230 plus whatever I'm carrying.

    Are you 100% sure they're pinch-flats? Check the hell out of your rim, and also check for debris stuck in your tire. After my latest round of flats I did a very careful assessment of my tire only to find a few tiny pieces of glass stuck in the tire such that they just poke through when the tire is loaded, causing occasional flats when the tube eventually wears through. As suggested by another member of this very forum, it can be helpful to keep track of your tube's position relative to the tire and wheel, so you can use the location of the hole in the tube to show you where in the tire/wheel to check.

  31. #31
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    Sanath,

    The rims and tires are fine. No, the tires are not getting pinch flatted during installation, not unless the pinch flats can hold perfect pressure for 1-3 weeks before going limp overnight. Thanks.

  32. #32
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    As described above, debris embedded into a tire's casing can slowly work its way through the tube. Likewise, a worn rim strip can slowly result in the same.

    Are you finding the exact locations of the pinch flats? It is not uncommon for the rim to ding when you pinch flat. If no rim ding, then possibly some damage or scuffing of the tire's sidewall. I am assuming when you say you're getting pinch flats that you are getting the paired snakebite holes in your tube?

    Also, the manner of discovery seems strange to me. Finding that your tires have gone flat overnight? Whenever I've had a pinch flat, it's something I find INSTANTLY. There is no question about what caused the flat. I hear the rim hit something solid, and usually feel it, too. Then the tire goes flat in a matter of seconds. Tires going flat while the bike sits overnight are usually something else - a puncture from some kind of debris, especially something that's embedded and only barely pokes through. Re-reading through the thread, I noticed that you never said which tires you have on this bike. Some tires (especially stock tires on just about any bike) have thin, cheap casings and are prone to flats.

  33. #33
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    Tires are bontrager H2 Plus. 700cx35mm

    A number of pinch flats yes, snakebit, some plain old flats very slow. I always inspect after a flat.

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    I do want to note, I really do appreciate all the advice, and I have some things I'll be checking/doublechecking (like the accuracy of my pressure gauge.) However, this project is scrapped. I thought I'd said as much yesterday. I'm not convinced of the likelihood of satisfactory results and will not be sinking money into it. I continue to communicate, because I continue to learn, and you guys are just awesome. However, I really feel bad at this point. I feel that I'm wasting your time, and that to me is disrespectful. Thanks.

  35. #35
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    ^^ I think you misunderstand "pinch flat". It is from hitting something like a pothole or other surface imperfection that pinches the tube between the collapsed side wall and rim and often occurs on both sides so can be called "snakebite". Too low a tire pressure with too high a load will cause this. Higher pressure mess up the ride, so there is a tire pressure/comfort/flat tradeoff. Sharp edges in the rim can make this more likely. I have even had the rim tape move into the spoke holes enough to give a rubbing wear on the tube that blows with the first stone I did not dodge that hit that spot.

  36. #36
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    Brian,

    Unfortunately I'm familiar with pinch-flats. I apologize for some of the vagueness in my posts which has caused this confusion. I haven't touched this bike in about 2 years, (since I got my SS 29er.) These issues come from that time when I rode it, and are among the reasons I was glad to put it away. The recent dilemma was weather I felt confident in solving the harshness issue and thus make it viable to bring back into service. Right now, it has no drive-train: cranks, pedals, chain, chain-ring, cog, tensioner, they'd all need to be replaced, before it touched pavement. So, please forgive the vagueness of old memories trouble-shooting a troublesome bike.

    Aside from the possibility that my gauge is faulty, the only other possibility that would give me any hope at all is if the tires on it turned out to be real junkers. A strangely obvious, yet at the time overlooked possibility.

    Thanks guys.

  37. #37
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    The tires sound like the cheap stock ones. Replacing them would not be a bad idea. Get the gauge checked, too.

    As many have said, 90 psi in 35mm tires should not be necessary to avoid pinches at your weight. I can ride 90psi in 25mm tires and avoid pinches and I weigh a more than you do. I suspect the gauge's accuracy to be questionable.

    But that doesn't address the comfort portion of your question. I find 32mm tires at around 60-65psi to be comfortable enough for my commute while avoiding pinch flats. Assuming your gauge to be inaccurate, it either means you think your tires are higher pressure than they are, or that you're inflating them far more than 90psi. If the tires are at a lower pressure than you think, they should be more comfortable than you state (if they were really low, it would explain the pinches) and if they're higher than you think, there should be zero pinch flats. Which gets us to questionable tire quality.

    But since the bike needs so much work, it does put you at a crossroads. It should be able to be put on the road as a reliable machine. Missing so many parts, is it worth that kind of money? Maybe if you could find some cheap donor bikes or a bike co-op just to get this thing rolling. If you can get this one back into working order, it would cost less than getting something else as a whole bike. Honestly, it would probably be easier to sell as a whole bike, also. This sort of bike isn't going to part out well, because most folks who might buy it aren't going to be interested in building a bike from scratch.

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