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Trek Help(10 posts)

Trek HelpHENRY K
Jan 1, 2004 7:37 PM
I have several bike projects going on right now. I removed an Ultegra triple from one bike figuring to install it on this extra 1990+-Trek 1400 that I aquired. I started to install the crank and immediately noticed that it was not going to fit. If I were to tighten it all of the way, the small chainring would hit the chainstay. Will this older bike frame/chainstay not accept a triple? Can this problem be remedied with a different bottom bracket? The bottom bracket shell on this frame is exactly the same size as the one on the bike that it was removed from. What gives?
re: Trek HelpAl1943
Jan 1, 2004 8:31 PM
You probably just need an Ultegra triple bottom bracket.
re: Trek HelpHENRY K
Jan 2, 2004 9:54 AM
I am using a triple b-bracket. It's the same triple that was being used on my other bike.
SpacersKerry Irons
Jan 2, 2004 5:43 PM
You can get spacers that move the right cup farther to the right (any decent bike shop will have them). It's curious that the rings hit the chain stay before you even tightened things up. How close were they on the other frame? Chainstays can be differently indented or shaped in anticipation of the bike having a double or triple, though that's usually not an issue.
SpacersHENRY K
Jan 3, 2004 8:07 PM
The triple crank and rings were not that close on the other bike. I tried the triple again tonight (just in case I was seeing things) I cranked it up tight and it did not quite touch but it was so close that there was no room to get a chain past the chain stay. I then reinstalled the 105/Biopace crank & rings that came on the bike. It was close but I was able to run the chain through without contacting the chainstay. So I am faced with the decision of buying a double crank & rings(dare I try to use the same triple bottom bracket? That might help keep things away from the chain stay, or it might make for a funky chainline) or maybe I could try the spacers. Could you please explain how they work?
Spacersrussw19
Jan 3, 2004 8:53 PM
Henry, are you sure you are not trying to put a 68 mm shell bottom bracket into a frame that takes a 73mm? It would go all the way in and more so than the bottom bracket is meant to. It could explain why you are running the crank too close. If you are unsure, I would take it to your LBS and let them look at it. It sounds like you have something odd going on, but without seeing it, it would be tough to tell. Might want to take it to someone you know who can get their hands on it to see what's up.

Russ
SpacersHENRY K
Jan 4, 2004 4:33 PM
Russ, Both shells are 68s. I have put both bottom brackets side by side and they are very close in width except that the Ultegra triple that I want to switch has a little longer spindle than the spindle on the double 105 that I removed. Thanks for your help. BTW, how do those spacers work?
Now I'm a bit confused!Kerry Irons
Jan 4, 2004 6:07 PM
How is it that the chain would be wrapped around the chain ring an touching the chain stay? This would be most bizzare! Or are you just using this method to point out how close the chain ring is? IMO, as long as the chain ring doesn't touch the chain stay and your chain line is good, this is not an issue. Regarding the spacers, this is simply a 1.37" "washer" that is placed between the frame and the right hand cup. When you snug up the cup, the BB ends up that much farther to the right. Check your chain line - with a "perfect" chain line, the middle ring of the triple should be dead center on the middle cog in the back. it's not really necessary to have a perfect chain line, but it is a starting point. If the middle ring is closer to the frame than the center of the cassette cogs, then the spacer is called for. Even if the middle ring is centered, you can still space things right with the spacer. Any decent bike shop will have these spacers.
You are correct,HENRY K
Jan 5, 2004 5:11 AM
with your assumption in your third sentence. Thanks for your interest.
I can't get my chain between either...TFerguson
Jan 5, 2004 8:02 AM
and it's a touring bike "made for a triple". Well, actually it can go through and did so with chain suck. I had a he!! of a time getting it back out thuogh.

TF