dwguy

I have a Raleigh Racing USA Grand Prix and it has the Suntour aRX parts on it. I think of the drivetrain is original, but I had to find the original, or a similar, Raleigh crank, since the last owner put some single chainring crank on the front.


Anyway, I was messing with the limit screws on the front derailleur, and there's no way for me to get the derailleur from coming out too far out. I can pretty much push the chain off the big ring, away from the bike, like the derailleur was built for a triple. Was this how these components were? Do I just have to be aware of how far I move the downtube shifters? Or is there something I'm missing?


Thanks in advance all!

dwguy

No response and I'm thinking this query would have done better with a picture

mstateglfr 

Your pic shows the limit screw is hitting the plate and the dersilleur isn't pushing the chain off the large ring. The limit screw looks like it can go further in, but it obviously can't. Thats odd.
Is the bottom bracket spindle original? If its shorter than what the crank should use, then the front derailleur may effectively push too far when its simply doing what it's designed to do.

HTupolev

I don't have any aRX components, but I have a SunTour BL front derailleur from 1983 that has its limit screws in a similar position. On my derailleur, there's a tab that the high-limit screw makes contact with, which is mounted on the parallelogram pivot above the derailleur cage:



It's actually able to pivot on the pivot: when the high-limit screw isn't jamming against it, it can be freely rotated within a small range of motion.

Edit: Here's the derailleur from the side.



The little metal object sitting in the notch below the head of the high-limit screw is the tab thingy.

seypat

Have a mod the thread to C&V. You will get more responses there.

dwguy

Thanks all, esp HTupolev for the pics. I went back and looked and it does look like something snapped off where the stop for the upper limit would be. I guess I'll just live with it.