Bicycle Mechanics - Help With Old School Downtube Suntour shifters

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Brandon286
01-01-10, 07:53 PM
I just picked up an old Fuji S12-S. I cleaned and regreased everything, now my only issue is that i cant get it to shift correctly. It has old suntour downtube shifters, and a 6 speed rear cog. I know this may sound dumb, but how many gears should each of the front chain rings be able to shift to? The reason Im asking this is because i saw a video about how, a 21 speed bike is theoretically more like a 12 speed because in order to shift into all the gears, the chain angle would be too great. So can anyone tell me what gear each of the 3 chain rings are supposed to shift to, and how to get it set up right? And on another note the brake hoods look like burnt cheese, does anyone know where i can get a set of replacements, they are Dia Compe brakes. Thanks
http://i60.photobucket.com/albums/h10/Brandon2286/SDC10333.jpg
The only issue? Have you tried riding with those saddle and bar angles?
WashWizards727
01-01-10, 08:05 PM
This bike should be able to shift into all the gears. Some of the gears may not sound as smooth as the others such as when you are in the big chainring in the front and the big one in the back. It shouldn't be that hard to adjust if you have friction shifters. If they are index, try switching them to friction by turning the D-ring on the side of the shifter. As for the brake hoods, check your LBS. You probably have the kind where the cable comes out of the top of the brake hood, not under the handlebar tape. These might be harder to find.
Replacement hoods for that bike can be found all over. Niagara sells them for less than $7 a pair.
If that seat is at the height you ride this bike, then the frame is too big for you.
Brandon286
01-01-10, 08:11 PM
hmm, ill have to really play around with them then, there is a bit of slack in the cable as well, i tried really hard to get rid of the slack but there still is a small amount. yup they come out of the top the LBS told me 30 bucks and I said no thanks ill go somewhere else thats nuts, maybe online somewhere if someone can give me a link? and I havent ridden it yet I just got it, and am making sure everything is clean and ready to go before i tweak any kind of seat or bar angles.
beech333
01-01-10, 08:21 PM
Nice old Fuji. I love the cranks.
$30 bucks. The last time I bought hoods, they were about $5/pair at a LBS.
Per your question about shifting...are you unable to shift to all of the gears or are you asking if you should shift through the whole rear cluster while in each of the front chainrings?
Brandon286
01-01-10, 08:27 PM
Nice old Fuji. I love the cranks.
$30 bucks. The last time I bought hoods, they were about $5/pair at a LBS.
Per your question about shifting...are you unable to shift to all of the gears or are you asking if you should shift through the whole rear cluster while in each of the front chainrings?
yeah I can only shift to certain gears with the front chainrings, the biggest will shift up like 3 or 4 gears, the middle the same, and the smallest only 1 or 2. I Like the cranks too they polished up really well and look cool. I have Nishiki that I bought and it has a 7 speed rear cog and the top cog has never been used its still shiney and i spent FOREVER trying to get it to shift to that gear and it wouldnt. these shifters can be quite trickey
Brandon286
01-02-10, 07:28 AM
so any suggestions?
MichaelW
01-02-10, 08:40 AM
Still not sure what your problem is.
Does the rear mech simply flip back after you change to a gear?
Did you lube all surfaces of the friction levers (the key word is friction)
Is there lots of noisy chain rub due to the chain angle?
Do you need to trim the front mech when you change the rear?
You should be able to use all six cogs from the middle ring, I reckon... make sure your rear derailleur's limit screws are properly adjusted, and your friction lever isn't slipping, and you should be sorted.
Also, I hope you're at least about 6'8"...
WashWizards727
01-02-10, 12:14 PM
Take the cable out of the rear derailleur and while spinning the cranks, try pushing the rear derailleur with your hand to the gears that it does not reach. If it does not reach, try loosening the limiting screws if they are not at the loosest already
bigvegan
01-02-10, 01:22 PM
so any suggestions?
Yes, check the derailleur cable tension, then make sure the limit screws are set, then fine tune by adjusting the barrel screw on the rear derailleur.
Check sheldonbrown.com if you need help, or just take it into the bike shop and pay them to tune it up properly.
mcgreivey
01-04-10, 10:41 AM
...And also, if the rear der (or front, for that matter) seems sticky when you move it with your hands, it may be dirty, and need a good cleaning. If the RD pivots are lubricated with grease, the old grease could be caked up.
And what condition is the cable housing in?
Is there any rust anywhere?
Do the shift levers move freely? They could be gummed up inside, as well.
If all parts are properly lubricated and moving as they should, then the only adjustments should be the cable tension and high/low stop adjustments (and if the shifters are indexed, then barrel adjustment to fine-tune the indexing, once the other adjustments are where they should be). Maybe also the b-pivot screw, if that's been fiddled with, or if you've changed to a different-sized cassette/freewheel.
cyclist2000
01-04-10, 11:40 AM
Brake hoods google dia-compe brake hoods and your will see that amazon have them for under $10. as for the shifters start the setup from the beginning, starting with both levers as forward as possible, adjust the fd and rd set screws as necessary, then loosen the cable clamps on the derailluers and pull the slack out of the cables.
Brandon286
01-11-10, 08:57 AM
Hey sorry for the late reply to this thread, I appreciate all the awesome advice I have received. It took me a while and alot of headscratching but I managed to get everything synced up and it shifts perfect. I just replaced the cables, and started from scratch which took alot of the frustration I was having out of the equation. I got the brake hoods off Ebay for 10 bucks, but had to modify them a bit to make them work (no biggie just a little razor knife work). Heres a link to my update, and some new bikes i got last night. Thanks again guys!
http://www.bikeforums.net/showthread.php?614355-3-older-road-bikes-I-just-got-check-em-out!
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