Classic & Vintage - RD woes... need some wisdom

The Suntour Cyclone friction RD on my 86 schwinn keeps wanting to jump in to a higher gear while riding, mainly when i'm straining to get up a hill.

I have adjusted and adjusted and basically tried everything i know to do.

The bike has a new shimano 13-28 FW, new shimano 6-7-8 chain, new stainless cable and a new piece of cable housing from the rear frame to the RD... it almost seems like its too slick and not enough friction the way it slips.

PLEASE HELP!! :twitchy:

~andy

Slipping often occurs at the shift lever. What's that setup like on your bike?

Neal

Slipping often occurs at the shift lever. What's that setup like on your bike?

Neal

+1. Surprisingly you'll need thoroughly clean all of the shifter internals and then lubricate everything. Sometimes on rare occasions a flexy frame can cause ghost shifting into a higher gear.

OK, will try!!

thanks guys

~andy

Oh, I just forgot in my original post, the bike originally had a suntour 6 spd fw, and the shimano is 7 spd... would that contribute at all?

~andy

You should really run a narrow chain with your 7 speed block. The regular width chain, if that's what you have on the bike, might be more prone to ghost shifting (because of the narrower sapcing of the rear cogs) if you get some rear frame flex while climbing. Try somethinhg like a narrower SRAM modern chain to see if the ghost shifting dissapears.

Chombi

+1. Surprisingly you'll need thoroughly clean all of the shifter internals and then lubricate everything. Sometimes on rare occasions a flexy frame can cause ghost shifting into a higher gear.

Do not lubricate the shifter internals!!! +1 on the frame flex ghost shifting.

Add a little friction to the friction shifter.

+1 to the notions re: the shifter may be at fault, and that flex can cause it, BUT does the ghost shifting only occur in one of the rear cogs? Did you adjust the limit screws?

-rob

Add a little friction to the friction shifter.
+1.............clean and LIGHTLY lube everything; then add friction enough to maintain your shifter/derailleur position.......

+1.............clean and LIGHTLY lube everything; then add friction enough to maintain your shifter/derailleur position.......

sounds good, i wondered if i could tighten it up a little.

will try all these things, btw i have a new shimano 6-7-8 speed chain on there, just installed yesterday

Thanks guys

!andy

be sure to keep track of the position and direction of the friction plates in the shifter; if you've never done it before.....it can be a PITA if you get them out of order. In fact; I would recommend doing one side at a time.....in case you need to use the other for reference...

don't ask me how i know these things......:)....

One time I took a shifter apart, cleaned it, and lightly lubed it. It never held a gear again, no matter what I tried to do. Be careful lubricating DT shifters.

+1 to the notions re: the shifter may be at fault, and that flex can cause it, BUT does the ghost shifting only occur in one of the rear cogs? Did you adjust the limit screws?

-rob

No, it occurred in several gears. I'm definitely thinking shifter needs more friction now, I'll post back with the outcome tomorrow probably. Thanks everyone

~andy

One time I took a shifter apart, cleaned it, and lightly lubed it. It never held a gear again, no matter what I tried to do. Be careful lubricating DT shifters.

Hmmm, good to know!!! can i just tighten it up a little? doesnt it have a screw on the side?

~andy

Hmmm, good to know!!! can i just tighten it up a little? doesnt it have a screw on the side?

~andy

Depends what kind of shifter it is, but just try tightening it first since that's easy and non-intrusive. It's highly possible that's all that's wrong.

Hmmm, good to know!!! can i just tighten it up a little? doesnt it have a screw on the side?

~andy

depending on the brand it may have a "D" ring (see pic) on the lever that you can tighten by hand. It may simply need adjusting. I'd sure try tightening it up before I took the shifter apart....

188275

Hmmm, good to know!!! can i just tighten it up a little? doesnt it have a screw on the side?

~andy

I think we've been assuming you knew about adding friction. The screw in the shift lever can be tightened or loosened to add or detract friction. What I do is shift onto the smallest cog, then push the shift lever foward about half way not turning the crank so the chain stays on the smallest cog. the shift should stay half way forward on it's own. If it doesn't, tighten the screw until it does. Then loosen it to see at what point it releases and moves back on it's own. From that point I tighten until it barely holds and then another quarter turn. Test ride with a screwdriver handy and tighten while riding if necessary.

I think we've been assuming you knew about adding friction. The screw in the shift lever can be tightened or loosened to add or detract friction. What I do is shift onto the smallest cog, then push the shift lever foward about half way not turning the crank so the chain stays on the smallest cog. the shift should stay half way forward on it's own. If it doesn't, tighten the screw until it does. Then loosen it to see at what point it releases and moves back on it's own. From that point I tighten until it barely holds and then another quarter turn. Test ride with a screwdriver handy and tighten while riding if necessary.


:thumb:

AWESOME! will do. Yes, this is the first bike i've ever had with friction shifters... I'm a total noob to them!!

Will try this tomorrow after work.

They are basic suntour shifters btw

Thanks so much !!

:cheers:

~andy

Once you know, it's simple. Basic Suntour DT shifters are excellent and can be habit forming.

The rear piece of cable housing you installed, is it linear indexing housing or standard spiral (brake) housing? Being a friction set up, using spiral housing may be in your favor.

The rear piece of cable housing you installed, is it linear indexing housing or standard spiral (brake) housing? Being a friction set up, using spiral housing may be in your favor.


actually the mechanic at the LBS installed it. to make a long story short, or long, i took the chain off the bike to give it a good washing and lube. I went down to the LBS for a quick link and we found that none of the links they had would fit the original chain on my schwinn. I told the guy to just throw on a 6-7-8 chain that they carried and be done with it. Then he talked me into the new cable and housing, telling me it would shift so much better. And he was right, it definitely shifts better, but now i am getting the ghost shifting.

im sure the housing he used is for indexed modern bikes...did not know that would make any difference, and stupid me, i didnt even save the original piece that came off the bike!!

I'm going to try to tighten up the shifter tomorrow. we will see...

~andy

Looks like the problem was the friction shifter for sure. I tightened the screw slightly this morning and it seems to be holding in the gears. Of course the real test will be on the road, but i'm 99% sure it was the shifter now. And it all makes sense now. Thanks very much for all the guidance, not being used to dealing with friction shifters, all i could think of was there must be something off with the derailleur or switching from 6 to 7 speeds had something to do with it.

Thanks Everyone!!!

:cheers:

andy