Bicycle Mechanics - '72 Peugeot UO-8 bent the forks, what are my options

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surveywaters
09-28-12, 09:22 AM
I came down hard on the front wheel today and bent the forks up on my SS trainer. The wheel is pressed into the front caliper. I am nervous about straightening it becausae I know it will be weaker than it was. I am not concerned about original on the forks and wouldn't mind something newer but it is a 'Frenchy'. What are my options, do I have any options?
Thanks
Bianchigirll
09-28-12, 09:29 AM
I believe you can simply buy a 1" replacement fork, english HS to match it and stem. Most shops usually have a selection of lowend SR stems removed from old road bikes for various reasons.
dsbrantjr
09-28-12, 09:33 AM
if you hit hard enough to bend the fork, how's the wheel doing? I'd have a close look at the frame as well.
surveywaters
09-28-12, 09:38 AM
The frame is good, the wheel is a bit out off true now but no dents. The forks are really thin and I think they may have been a bit week already.
With a replacement fork will the trail be the same? The forks stick way out past the headset.
I believe you can simply buy a 1" replacement fork, english HS to match it and stem. Most shops usually have a selection of lowend SR stems removed from old road bikes for various reasons.
Yes, a new fork along with a new ISO/BSC headset will work, but the OP will also need to replace the stem, and then most likely the handle bar. ISO forks & stems are 22.2mm (7/8") but the old fork and stem were 22mm and so will not fit properly into the new fork.
The issues of basic fork geometry are manageable. Even if the fork isn't identical, the rake and trail won't be different enough to worry about. But the OP needs to try to match the crown to axle distance fairly closely, especially if he's using 27" wheels (original to UO-8sm back in the early seventies). A modern fork built for 700c won't clear.
IMO- by the time the OP is done, he'll end up spending more than this project is worth. He might be better off trying to find an old UO-8 in decent condition to cannibalize for parts, or another decent looking old bike to recondition.
surveywaters
09-28-12, 10:07 AM
Is this (http://www.niagaracycle.com/product_info.php?products_id=415876)something like what you all are refering to?
Is this (http://www.niagaracycle.com/product_info.php?products_id=415876)something like what you all are refering to?
It'll do, but you'll need a new headset, stem, and probably handlebar. The headset would be complicated because the frame wants an ISO headset and the fork is JIS/27.0 vs ISO/26.4. You could have a bike shop mill the crown (about $20 more or less), or buy a JIS crown race to match the headset.
Try to find a similar fork prepped for a 26.4mm crown race, or ask Niagara if they can do this job for you and how much extra. However before actually spending a cent, work up a total cost so you can intelligently decide if the rest of the bike warrants the upgrade.
surveywaters
09-28-12, 11:16 AM
Forgive my ignorance, this is technical beyond my experience. When you say mill the crown is this refering to turning down the chubby section the crown race sets on so that a 26.4mm race would fit? If so, could I shave .3mm off that section and use the crown race included in this headset (http://www.ebay.com/itm/300781924502?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649)? I can't tell if one is include, however if not, the peugeot crown race is 26.5mm and could be used, correct?
Forgive my ignorance, this is technical beyond my experience. When you say mill the crown is this refering to turning down the chubby section the crown race sets on so that a 26.4mm race would fit? If so, could I shave .3mm off that section and use the crown race included in this headset (http://www.ebay.com/itm/300781924502?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649)? I can't tell if one is include, however if not, the peugeot crown race is 26.5mm and could be used, correct?
Ignorance is forgiven. Yes, you need to turn .3mm per side off the small raised seat at the base of the steerer. This can be done freehand with a file, but is very difficult, and best not attempted buy anyone not expert in precision filing. Bike shops use a tool made for the job, and as I said, Niagara might be able to do this for you (ask).
Headsets always include crown races, so that isn't the issue, but you cannot use your original one, because it won't match the rest of the new headset.
surveywaters
09-28-12, 11:41 AM
Thanks so much, I'll ask Niagra and call my LBS for price comparison. I think this does it, now I have messed up and found a threadless adapter which means new bars and stem too.
Thank you for your patience
Jon
Lazarus Short
09-29-12, 07:55 AM
I had a UO-8 of about the same vintage. I was told back in those days that those forks were delicate, but had no problem with them. A few years later I got a PX-10 which I still own. But I digress...
You could scrounge around bike shops to find a fork. You could use a non-French fork and an upper race (the part with threads) which would be compatible with both headset and fork. You might even get lucky and find a French fork of the right length. However, why not upgrade at this point? The world is just full of used bikes these days, and as I recall the UO-8 was no great shakes.
Bianchigirll
09-29-12, 08:11 AM
Thanks so much, I'll ask Niagra and call my LBS for price comparison. I think this does it, now I have messed up and found a threadless adapter which means new bars and stem too.
Thank you for your patience
Jon
Odds are on a replacement fork the difference in price will not be an issue. Again a used fork is an option and you need to use your LBS once in a while any way. One day you'll need something dones on the spot and if you are know as a "mail order guy" guess who goes to the back of the line.
FBinNY vrings up a good point especially if now you are talking about a threadless adaptor and threadless stem. You may be better off just finding another old OU-8 to fixiefy.
Also did you check the frame for damage?
cny-bikeman
09-29-12, 08:23 AM
I came down hard on the front wheel today and bent the forks up on my SS trainer. The wheel is pressed into the front caliper. I am nervous about straightening it becausae I know it will be weaker than it was. I am not concerned about original on the forks and wouldn't mind something newer but it is a 'Frenchy'. What are my options, do I have any options?
Thanks
I would recommend a suspension fork on a bike more suited to wheelies or jumps.
surveywaters
10-07-12, 09:17 AM
I appreciate all the help guys. I put a $30 generic replacement 1" fork on the bike and a $5 Tange-Seiki ISO headset. The races fit the frame tube perfect, but I did have to mill down the crown race seat as described; that only took about 10min with a mill bastard and a steady hand. The bar stem is a real nice and snug fit with a lager can wrapped around it. Everything fit well and looks good.
http://i799.photobucket.com/albums/yy279/surveywaters/1972%20Peugeot%20PX-10/DSCN6431.jpg
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