apex mxr100 engine vibration

[HPM Racing]

Hey everyone. I'm new here, but I have been messing with my banshee for 15years so not a total newbie to the quad scene. I just picked up a 2010 mxr100 for my son after he kept breaking axle carriers jumping with his lt80. I have a couple of questions about the apex quad. This is mostly going to be a play quad since mini quad racing isn't that big out here in Arizona. I just needed to upgrade him and this seems like the best platform to start with. The quad needs some tlc, worn a arm bushings, swing arm bushings, brakes, clean up and adjustments. Planning on doing the whole thing over just need some help getting started. Anyone have any success fixing the vibrating motor? From what I see it is very common in these motors. Would a full circle balanced crank help? I am going to add some bar ends to the handlebars to help the vibrations but that is just masking the real issue. How come I don't see any kits for the 100? Seems like they all stop at 90cc, would it be better to downsize the motor? Do the pipes and upgrades work for the 100cc or should I just down size it to a 90 for the better parts availability? I wasn't planning to dive into the motor but if I can lower the vibrating I will.


Any help will be appreciated.

[ontargetracing]

HPM,

Yes they do vibrate.. so do the stock 90's. The stock bars are also crap..! you can put a set of good bars on it like ATV Four Play or Flexx bars and that should do away with your vibration... A better quality anti vibe stem may help also. I am not sure if a built motor vibrates as much since we have never had one in a chassis with stock bars on it. More parts are generally available in the 90cc range because that's usually what most race classes allow. There are some larger 95 and 98cc kits around but not very popular in the US. The stock pipe is pretty good for a stock motor. If you want to make it faster I would start with a Max Speed kit from gforce. Porting the stock cast iron cylinders also works well. To take advantage of most performance pipes out there you need to create more RPM's and you cant do that with a stock ignition.. so a pvl would be needed. So if you want a really fast reliable stocker: Over Range kit, ported cylinder, pvl, exhaust and possibly a good intake and reeds... but IMO I will say in stock form a properly setup apex will be 10x the machine the LT80 was.

[HPM Racing]

HPM,

Yes they do vibrate.. so do the stock 90's. The stock bars are also crap..! you can put a set of good bars on it like ATV Four Play or Flexx bars and that should do away with your vibration... A better quality anti vibe stem may help also. I am not sure if a built motor vibrates as much since we have never had one in a chassis with stock bars on it. More parts are generally available in the 90cc range because that's usually what most race classes allow. There are some larger 95 and 98cc kits around but not very popular in the US. The stock pipe is pretty good for a stock motor. If you want to make it faster I would start with a Max Speed kit from gforce. Porting the stock cast iron cylinders also works well. To take advantage of most performance pipes out there you need to create more RPM's and you cant do that with a stock ignition.. so a pvl would be needed. So if you want a really fast reliable stocker: Over Range kit, ported cylinder, pvl, exhaust and possibly a good intake and reeds... but IMO I will say in stock form a properly setup apex will be 10x the machine the LT80 was.


Thanks for the reply. Already looking into the bars solution. Was hoping for some info if a full circle crank would help also. And has anyone installed the bottom motor mount?

[ontargetracing]

sorry, I cant help you there.. we never messed with the stock motor or used the lower motor mount, it usually just gets in the way of aftermarket exhausts so we cut it off.