Hi! Got some Q's about an 07 MXR 90

[TechDad]

I just purchased a 2007 Apex 90 MXR for my son to possibly race this season.

What are the big things I need to look out for?
Replacement parts to have on hand, etc?
Safety issues? places in the frame to lookout for?

The gear box has been updated. Something about landing with it pinned breaking gears...

Thanks!!
Darin

[XXX -rider]

what type of racing ?

[TechDad]

Originally posted by XXX -rider
what type of racing ?

AMA District racing on a track. What other types are there? Circle?

[marsrace2]

motocross
Hare Scrambles
Flat Track
TT
XC
Enduro

[DVXchic]

In 2008 they put a slipper sprocket on the cs, this is to avoid the tranny from breaking under load on landing. If your model does not have it, it is strongly recomended.
The frames weak spot is right above the chain, after a while of jumping and compressing the rear suspension so much, the chain will run along the frame and eventually cut through it. i have seen people set up rollers to prevent this. this also happens on DRRs.
We have a few customers that keep an extra tranny, just in case. can be changed righ at track with right tools. and other stuff like filters, belts, springs, etc.

Hope this helps

[zach R 7x]

if you are going to race and it is your sons first time ,i would highly suggest the slipper sprocket. if a gear breaks it will more then likely take all the gears with it and possibly crack motor case ,believe me this happens alot!it will save you alot of headaches and money down the road.
it would not hurt to keep a set of gears in your trailer,they can be changed out at track rather quickly.

save yourself alot of headaches down the road and have your frame gusseted ,the apex comes with factory gussets but they are not enough.

i would purchase a extra air filter and change it out regularly.

purchase a ztr frame saver ,it will save that spot on the frame that the chain rubs, it's a great product.

my suggestion is to make as many friends at the track as you can, because you can never carry enough spare parts!what you don't carry they might.(':D')
just my.02cents
tim

[TechDad]

Thanks for all of the good advice. My chain doesn't touch the frame anywhere....it does have a plastic sheild covering the swing arm where the chain hits sometimes.

I dissasembled the clutch assembly the other night, after smoking it pretty good, and the only damage was the clutch bell housing was a little purple from the heat. I was actually impressed with the quality of the parts.

Had fun in the snow the other day. This quad is amazing.

[tyler70t]

Your chain WILL rub the frame as soon as you start jumping the quad, guaranteed!!! Look @ my post for "frame saver needed "and check out the pics. Read what others had to say and spend the 40 bucks on a ZTR frame saver....Just my opinion. Anyone else agree?:macho

[quadnana7]

Chain will cut through the frame like a chainsaw through a tree.
Don't race without it!

[zach R 7x]

buy the frame saver ! you won't regret it .

that purple color is not a good thing! it usually means your clutch is slipping and robbing hp.

[TechDad]

Originally posted by zach R 7x
buy the frame saver ! you won't regret it .

that purple color is not a good thing! it usually means your clutch is slipping and robbing hp.

Yeah, thats why I said the damage was from me smoking the clutch. I found out I was too big to ride on some of the hills on our property. The clutch never slips under normal circumstances, especially with my son on it.

I WILL buy the frame saver. Everything is perfect right now, but i will take your word for it.....