Moulton APB Front Suspension Issues Fixed
#1
Senior Member
Thread Starter
Moulton APB Front Suspension Issues Fixed
After getting my Moulton a few months ago, and then riding it 300km per week since then, it began developing an annoying squeaking sound when the front suspension was cycling over bumps and whatnot. I dropped some oil down the steerer tube, and, not understanding Moulton's suspension concept, oiled the linkage on the lower end of the forks.
This solved the squeaking problem, but the bushings in the front suspension are not supposed to be oiled, and after oiling them, the bike bobbed up-and-down very noticeably. Another issue was a clunking sound as the bumper bottoming out. I learned that the responsiveness of the front suspension is regulated by the 6 "ny-lock" nuts holding the front linkage plates together.
So today I removed the suspension assembly from the fork (remarkably easy), cleaned up everything, reassembled it, adjusted it, and now it rides wonderfully. No more bobbing while pedaling hard, and no more bottoming out. I liked that the only tools necessary were an 8mm wrench for the nuts, and an Allen wrench to remove the brake cable. It's an ingenious design, and much more effective than I would have thought.
My experiences with the APB so far are all positive. It is remarkably stable, very smooth. It is very easy to upgrade. So far I have installed a complete Dura Ace 7700 driveline with a Capreo cassette, which makes it a competent climber, and can still be pedaled on steep descents. It is not particularly light, but has gotten a little less portly with each upgrade. It's one of those bikes which makes you want to ride it.
This solved the squeaking problem, but the bushings in the front suspension are not supposed to be oiled, and after oiling them, the bike bobbed up-and-down very noticeably. Another issue was a clunking sound as the bumper bottoming out. I learned that the responsiveness of the front suspension is regulated by the 6 "ny-lock" nuts holding the front linkage plates together.
So today I removed the suspension assembly from the fork (remarkably easy), cleaned up everything, reassembled it, adjusted it, and now it rides wonderfully. No more bobbing while pedaling hard, and no more bottoming out. I liked that the only tools necessary were an 8mm wrench for the nuts, and an Allen wrench to remove the brake cable. It's an ingenious design, and much more effective than I would have thought.
My experiences with the APB so far are all positive. It is remarkably stable, very smooth. It is very easy to upgrade. So far I have installed a complete Dura Ace 7700 driveline with a Capreo cassette, which makes it a competent climber, and can still be pedaled on steep descents. It is not particularly light, but has gotten a little less portly with each upgrade. It's one of those bikes which makes you want to ride it.
Likes For 50PlusCycling:
#2
Senior Member
FYI, there are several spring stiffness for the front suspension and the washers inside the linkage plate can wear and must be replaced after a long time (the spring provides the suspension, the washers the damping).
The spring pre-load can be adjusted and the damping can be adjusted too by the tightening of the center bold of the two plates.
There are user manuals explaining all this, you should be able to find them by googling.
The spring pre-load can be adjusted and the damping can be adjusted too by the tightening of the center bold of the two plates.
There are user manuals explaining all this, you should be able to find them by googling.