K2 / Proflex Riders Group
General => Tech Forum => Topic started by: rakira2001 on August 20, 2008, 11:00:38 pm
-
came across a 756 in my brother's garage, elastomer in the rear shock is shot, has a rock shox front fork that looks like it's been on there since '97 or '98, and I can't find the bolts for the lower strut assembly, there's also no headset. Other than that it's a nice looking bike, componets appear decent (shimano deore). Is it worth repairing? Replacement rear shocks are pretty expensive. Thanks
-
i think the response from virtually every member on here would be a resounding `yes` its worth rebuilding, the ones that would say `no` would be the members that would want to buy it off you! ;) there have been many topics and threads on here regarding replacement shocks for the strut bikes and many people have made excellent adaptors to fit modern shocks on their bikes. if the frame is in good shape then modern forks and a modern rear shock will make it rideable for many years to come.
-
came across a 756 in my brother's garage,
I think you paid WAY too much for that bike to have these many defects. ;D
Honestly a cheap headset, and elastomers won't set you back too much.
Terry
-
Headset £15 rear shock £23 (rapid descent scotland) front shocks £50ish (half decent pair off ebay), less than £100 for an awesome type of bike that gets heads turning everywhere you take them!!! I've spent over £500 on three bikes two are still just frames with one being fully built and used, i'd always wanted a pro-flex from school now i'm 29 and can't stop buying the damn things. One tip buy anything you can that's retro, anodised or shiny they look amazing. GOT THE BUG BAD!! 857 coming soon hopefully with a trick paint job
happy riding Dave
-
ok well seeing as how I didn't pay anything for the bike I get the point. Any suggestions for a rebuild? I was thinking of replacing the rear elastomer with a genesis but I'm not sure what to do with the front fork. Does the 756 have a 1" or 1"1/8 steer tube? Steer tube on current fork is 1" but head tube measures 1"1/8. Also, does the fork and rear suspension need to have about the same amount of travel? The crank and chainring also are looking a little rough, so please any suggestions you might have would be helpful.
-
any idea too where I could find bolts to replace the ones that attach the strut to the swingarm? Auto parts, hardware store, bike shop?
-
any idea too where I could find bolts to replace the ones that attach the strut to the swingarm? Auto parts, hardware store, bike shop?
Bike shop should have them no problem. I think stem cap bolts are close to that length.
-
Questions questions questions... I think I've asked them a few times myself!
Here are a few tips from a slow learner. Take 'em or leave 'em.
- Get a 1-1/8" Fork.
Keep the front travel around 4" or less. More is okay, but the geometry gets a little weird. If you're cheap, like me, you can get a brand new 5" Suntour fork for $40. If not, you can get a new Fox for $750. They both bounce.
Strut to Swingarm bolts should be stainless M6-1 x about 3cm. Use button head cap screws. (Good for the ankles on the back of your stroke!)
Risse shocks are the best. You can get Noleen spring/damper combos on ebay pretty easily.
Check the cranks for free spinning, check the rings (esp the middle one) for "wallowed out" or broken teeth, check the BB for wiggle. If they're just dirty, clean 'em. If they're bad grab one of those discount XBB cranksets. If you're in CONUS, Jenson & CBO pump out RaceFace XBB cranksets for $110! You can go old new stock Deore from Nashbar for under $50 if you want to be old school-ish.
Make sure you disassemble, clean, grease, and reassemble the swingarm pivots.
Make sure you have enough seat post in the tube that you don't break anything. (4"+ I'd guess...)
Please take off the bar ends. (Unless you ride with a white styrofoam helmet.)
Ride it like you stole it! (Wait, you did steal it... good job!)
Cheers,
Will
-
FINALLY THE 857 IS ALIVE WHAT AN AWESOME RIDE
PRO-FLEX ROCK!!!!!!!!!
PEACE OUT BIG DEE! :) ;D
ALL PRO-FLEX'S SHOULD BE BUILT AND NEVER BE SENT TO THE SCRAP BIN! ANYONE THAT DOES SHOULD HAVE THERE GENITALS REMOVED PICKLED AND FED TO CHIPMUNKS!! BY ORDER OF SOME HIGHER BEING, or something like that? (it's amazing how a 20mile ride and 6 pints make you feel)(hic) KEEP THE BIKES ALIVE!!
-
ok well seeing as how I didn't pay anything for the bike I get the point. Any suggestions for a rebuild? I was thinking of replacing the rear elastomer with a genesis but I'm not sure what to do with the front fork. Does the 756 have a 1" or 1"1/8 steer tube? Steer tube on current fork is 1" but head tube measures 1"1/8. Also, does the fork and rear suspension need to have about the same amount of travel? The crank and chainring also are looking a little rough, so please any suggestions you might have would be helpful.
the headtube itself is indeed 1 and 1/8,there were specers in the original headset to be able to use the 1 inch givins forks they had heaps off.....
if you need a new BB the original is 68 x 110 square shank