DID Chains & Brake issue

[rd2005]

I bought a DID High Performance 428 Chain for my boys Apex 90cc quad. 4 races later the thing is stiff as a board & what looks like caused the trany gears to get eaten up! Needless to say I am not happy! Has anyone else had trouble with this chain? What chain do most of you all run? Also one other thing having trouble with the rear caliper locking down on the rotor...2nd race now with this issue. I've heard using a 300EX caliper & I've heard using a YFZ Rear Master Cylinder...which is best to fix this problem?

[FISH ON!]

Check your sprocket alignment before you go through any more chains. I haven't owned an Apex that didn't need some shims to get the sprockets aligned. We run the DID x-ring chain. That's their strongest chain but lots of folks don't like oring chains.

Your rear caliper most likely needs a cleaning. The two posts with rubber boots get dirt and grime in them. Take it apart, clean it up and put a small amount of grease in it. Otherwise, the YZ85 caliper is a good choice (dual piston) but requires a custom brake plate.

Hope this helps.....

[selbygirl]

plus check your swing arm on the bottom may be cracked . plus after you clean your chain you should lubercate it , and a tight chain will break a tranny , inspect your tranny gears and the needle bearings every so often , and are you running a slipper clutch or sprocket you should if your child is jumping, and if you are using a slipper sprocket , iwould use a silocone spray on chain somtimes oil can get on the slipper pads

[chunky0071]

If you have the red rear master cylinder that is way your rear brakes lock up. That master cylinder bypasses and builds pressure on both sides in turn locking the rear brake. If you have had to bleed the brakes to get it to roll this is what is happening.

[rd2005]

Ok the sprocket is in alignment. I looked & no cracks in the swingarm. Our Apex has the brass bushing/bearing not needles. We run a slipper clutch as well. I hadn't heard about the YZ85 caliper What is that off of? Also I have not had to bleed the brakes to get it to release & roll. I smoothed the 2 pins on the caliper but not cleaned as mentioned. I will do that tonight. I don't want to run an o-ring chain so what do you all use? Thanks

[FISH ON!]

Take a look at the right rear motor mount bushing. Those things wear out and the motor moves around under load. They should be replaced periodically. If the motor is close to stock that DID chain should be fine. Are you using a frame saver or is the chain diigging into the frame by the motor mount?

YZ85 caliper is a Dave Carter modification.

[rd2005]

Ok the motor mount looks worn...I have new ones I will put in tonight since transmission is out. I'm also going to put in bottom motor mounts as well. The motor is not stock. I was told to use the high performance D.I.D. chain but it just did not hold up. I do lubricate the chain often. I am using a ZTR Frame saver (no cutting into frame) & also have a chain tensioner.
Regarding the YZ85 caliper I want to get this right...do I need to get the whole thing (cylinder, pedal, rear caliper) or just replace the caliper with modification you mentioned? Thanks for the help.

[RichC]

I had the same problem, mine turned out to be master and rotor was concaved. Replaced with a yfz 450 master and replaced rotor, never had a problem since.

[fomospede]

chains will get stiff if they have been hot
im suspect that the chain may have been to tight
at some part of the suspension stroke