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  1. #1
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    Doing a conversion...advice please...

    I have decided to convert my old beater into a single speed rig. I've ridden the hell out of this bike since buying it new in 1993. It's a cromoly framed rigid bike I bought from my LBS, its been worth every penny of the $400 I dropped on it at the time, but cant bring myself to replace all the parts that need replacing. I bought a new bike in August and plan on using this converted bike for winter riding.

    I'm starting the teardown today. This is my first conversion, so I may post lots of stupid questions

    First one:

    Are the dropouts on this frame horizontal enough to not require a tensioner? My understanding is that it is.



  2. #2
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    Quote Originally Posted by Voodoo Child
    First one:

    Are the dropouts on this frame horizontal enough to not require a tensioner?
    Yes. So far, so good.
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  3. #3
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    Yeah, you should be good on the dropouts. Although when I use dropouts of that length and style, I try to put the wheel more forward with my ratio choice to allow it to be tensioned to take up the slack in chain stretch. You can always dremel the dropouts longer as well. It sucks having a loose chain and the wheel all the way back. I ride a very fine line on one of my bikes to get clearance for a 37mm tire. The wheel ends up all the way back and the chain a little slack after it stretches a little bit.

  4. #4
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    More questions...

    Let me preface all of this with the admission that I'm not really all that knowledgeable about bike repair. I'm trying to use this conversion as an opportunity to learn. I do the basic stuff, change brake pads, tires, tubes, handlebars, nothing complex. I'm also trying to do this on the cheap.

    I've got the bike stripped down as far as I can get it at the moment and have a few things to run by you folks.

    The last time the chainrings required replacement, I took it to the bike shop and went cheap. My reasoning at the time, was I was hardly doing any offroad cycling anymore, mainly bike paths with the family and commuting. They threw on a Shimano Altus C20 chainset....for $30 total. Made me happy and got rid of some low end junk laying around.

    I think the crank arm and the 3 piece chainring are all one piece....can anyone confirm? I dont have a crank extractor, so I cant take it off to check. The middle ring looks like it is attached, no spider or bolts to be seen. The outer and inner rings are riveted to the middle. They are 48/38/28 rings.

    What are my options? I'm thinking of yanking the thing off, drilling out the rivets on the outer and inner rings and running with the 38.





    I had been having some really frustrating ghost shifting issues on the rear and no matter what, couldnt adjust the deraileur to eliminate them. I assumed it was just a farked up deraileur. The cassette seemed fine. This was the final straw in convicing me to convert to SS. Now that I've got it apart, I know where the shifting problems came from, my rear axle is bent on the cassette side and the bearings are loose. I've got about 2-3 mm of play on that side. I dont know what came first or how it happened, but I'm assuming the bearing loosened up allowing the axle to flex and ultimately bend. The axle can be replaced correct? I dont yet have a chainwhip or the shimano lockring adapter to take it apart and inspect it closely.



    What are your suggestions for the rear? Was planning on ripping the cassette apart, using a 20 cog and pvc pipe for spacers. LBS has a conversion kit, spacers and cogs for $30.....but I think the cogs are 16/17/18, which would be a bit steep with the 38 front ring no? Any advice? Should I get a BMX cog?

    I'm hoping I can find a bike shop open today to buy the tools/parts I need to finish this and get out for a ride this weekend.

  5. #5
    US Army Vet-Airborne 11B
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    sorry so long...i got writers cramps:p

    i've personally never had the bent axle problem,so i can't really help ya there,other than me thinkin "he should be able to replace that",but i really am just guessin at that (since i don't have any experience there).

    i started learnin to do my own work most of this year too (besides takin a 70-75% pay cut this year,thas sumthin i always wanted to do),and i've really been enjoyin it.you'll find that tools get bought as ya need em.ya could jus buy an elaborate kit that has all ya needs in the box if ya has the scratch to spare,but it's not really a have to.i find a coupla good manuals came in really handy (plus i loves ta read...despite mah hillbilly accent ),and a coupla good ones are park's big blue book of bike repair by park tools (duh),and "zynn and the art of mtn bike repair" by lennard zynn (he also has a road bike book,i'm told).the zynn book wuz 'specially helpfull to me,and an entertainin read ta boot.

    yes yer dropouts will work fer tensionin yer chain (i'm eventually gunna get around ta convertin/buildin up that old diamond back frame and schwinn hybrid as SS's,and both of em have similar drops...eventually ),and the pvc pipe spacer thing is a "why the heck didn't i think of that" fix...good idea.for the mean time,ya could jus run the cassette as is and pic a gear that has a decent chainline.

    if drillin the rivits out of the crankset ta get to the 38t doesn't work,budget priced (read:inexpensive) cranksets can be found.bike nashbar has a house brand of certain parts,and they have a crankset for (usually) under 50 bux that has removable/replacable rings,but the middle is 32t.they may have a 34-38t replacement for it,not sure as i run a 32t.i been meanin to pick one of those up myself fer buildin up a nashbar steel frame i bought almost a year ago (been hangin as decoration )...eventually i'll get a round to it .

    good luck,and welcome to the ranks,and post some pictures-we all love bike porn.
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  6. #6
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    It may be easier to keep it as a grocery getter and spare ride for pals with the gears. Sounds like it may end up as a money pit! A new or used SS will be more cost effective in the long run.
    The wheel is a extension of the foot

  7. #7
    Ride Responsibly
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    ask around for some old square taper lx crank set with a bottom bracket and a set of dust gathering wheels, friends bound to have something layin around, while yer at it ask for there help setting up the rear cog to be in line with whatever frt ring you use.

  8. #8
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    What kind of frame is that?

    From the looks of the welds, and the dropouts (for 1993, those droouts are very dated and look too thin for hard riding), the frame looks like it was made out of hi-ten steel which is weak, soft, and heavy.

    Also, you should get another rear wheel because the gears on the back are a freewheel. On a freewheel, the whole assembly threads on to the hub vs. cassette gears which slide on to a cassette body which you CAN use a spacer kit on, (the standard of all geared bikes today). And simply threading a bmx freewheel on the hub will throw your chain line off way too much. Oh, and the spokes are not stainless and will easily break, and I bet the rims are steel (vs. alum), and will bend easily.

    But if that stuff doesn't matter for now, here's how you can turn it into a single speed with little investment, but know it won't hold up well riding it off-road:

    - Leaving it like it is, ride it in various gears while leaving it in the middle chainring up front until you find what gear will work for a single speed. Find one you can climb hills on ok.

    - Cut the chain to length so it will work in the "preferred" gear.

    - Now pull the wheel back until the chain is pretty tight making sure the wheel is centered when tightening it.

    - Take off any unecessary crap, (shifters, derailers, but leave the chain rings alone)

    - Go ride.

    * Note, you will have to leave your rear gears on there as is even though you're only using one of them. If you get into it enough, save your money and get a better bike. The frame and parts are not transferable towards upgrades.

  9. #9
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    I'm out!

    OK, so not knowing a whole lot about bike mechanics, I stripped it down, and took the rear wheel to a bike shop. Freewheel, so conversion kit is a no go. Suggestion was to buy a new wheel. I am not sinking money into this thing.

    I did buy a new axle, installed it myself and put the bike together, minus the front deraileur and shifter. Running middle ring up front, may still drill out the rivets and remove large and small rings.

    I tried running without rear deraileur but couldnt get a decent chain line that didnt sound like grinding metal. So back it went.

    So, thanks for the advice, but this one is done. It's back to a bike path bike. I learned a lot tearing this thing apart and failing in my conversion so it wasnt a total waste. Know how to replace a bent axle now and bike shifts smoothly again I know the difference between the newer and older style rear ends. I have a few new tools.

    After pricing out everything that I would need to buy to do a conversion and have a decent rideable bike, I'd be about 1/3-1/2 way to a new KHS Solo-One 29er SS. I love the idea of the simplicity of SS. Raced BMX a long time ago and remember how much fun it was to have a solid bike that just worked.

    I'll be back

  10. #10
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    F it man. You just learned a lot of valuable stuff about bikes that you can only get from experience. We'll see you soon I'm sure.

  11. #11
    Avenger of Evil
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    Don't give up.
    My rear wheel was the same as yours. All I did was purchase a Shimano BMX freewheel and threaded it on. Works like a charm.
    Famous Last Words....."Hey, watch this!!"

  12. #12
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    BMX freewheel

    Bike shop mechanic said it will be hit and miss if a BMX freewheel will give a decent chainline, so I abandoned the thought. One lesson I learned a long time ago is to stop throwing money at crap, you usually end up spending more than just buying new.

    Oh and to answer some questions.....the frame is a Canadian made cromoly from Leader/Minelli. Not high spec, but passable for what I used it for. This was my first bike purchase since I stopped BMXing. I specifically asked about the frame and paid the $150 more for the full cromoly frame bike......only because at the time when I raced bmx, if your frame wasnt cro-mo, it was crap

    The wheels say Weinmann - Made in USA. I *think* they are of decent quality no?

    I rode it yesterday, found a gear that works for the area and will lock up the rear deraileur and remove shifter. So it's a redneck SS bike for me! You know what? I found a hill that I normally ride all grannied up on my new bike, spinning up the hill. I rode it with 38/20 combo, stood up and mashed my way up. I actually think it was easier in some strange way....

    Any idea what a decent price for this would be: http://stcatharines.kijiji.ca/c-buy-...QAdIdZ33479743

    That Giant should be convertable no?

  13. #13
    NormalNorm
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    Hey voodoo child, i sent you a pm.

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