Hello. Just bought a 2001 KLX 300R with kick start only. I know there are some issues related to the KACR system, leading to break up the idler gear, because of the play in the gear bushing. I want to make MARCELINO CAM MOD, even if I will got less advantages than the 250s. Can I remove the ACR system? It will lead to worse starting? Will make the idler wheel to break up faster? Or I can go safe without ACR? Can I also ask if the 2003 and on idler wheel fits plug and play into my 2001 or I need to rebushing? And also how to shim correctly the idler wheel? Thank you very much!

 

Try it, take off the ACR spring and see how it starts with the ACR disabled. I know a big single can be started without a compression release, it's just a bit harder and takes a bit more time. I could bring my SR500 up to TDC, then slowly ease it over TDC (what is done by either a manual or automatic release) then let up on the lever and kick with authority. A bit more work, but doable. Not sure on the KLX300R trying to kick up and past TDC.

If you are concerned with the ACR shoes coming off you can do what the KLX650 riders, myself included, have done. The 650s were kind of known for having the ACR come apart and I had the spring come off mine twice. Pull the cam and restake the rivets just enough to take out excess side play with them still easily able to rotate out. Then look at the spring and think about which way it should be installed to avoid having the hooked end catch on anything and come off. I remember looking at the spring set up on my 650 about 20 years ago now, when the spring came off one time. I remember putting it on a certain way, but would have to look again to be certain this is a thing to do.

 

OH i remember you, because i was reading some old posts and reading. You right, there's a way to start up a 4T, my only concern is about the idler gear that can break up and cause disaster, i would swap for a 2003 reinforced gear. I know that the carburetor version with MCM mod don't require KACR retiming because it will be into easy start position by default. With injection models you ha e to retime CCW the ACR because it will be like the older carbd version. I would like to remove the ACR because I don't want things into my engine to fall apart and cause damages. Less part less risk. If you have some pics about spring mod please let me know. Thank you for your kind reply.

 

It does require retiming of the ACR with any of them. I would think it is possible that the gear issue may be more an issue with the ACR because it will be easier to "slap kick" it like a two stroke, just kicking away and if it kicks back that may be what is breaking the idler gear. If done properly any four stroke should have a very purposeful kick (for lack of a better term), where you make a solid effort kicking from the top, through the stroke, not just kicking like crazy like can be done with a two stroke.

I said take the spring off and see how it works, because you may or may not need it and the only way to tell is to disable the release. If you find there is no problem kicking away, you may be able to remove it entirely. Btu I don't know if you can. Either way if you do the MCM you will probably need to alter the position, so be prepared and read up on where it should be positioned in the MCM thread. Marcelino explains how and where it should be.

It's a shame there isn't a way to make the compression release manual, like the SR500.

 

Are you sure it requires retiming also in carbd version? I remember a guy who did on thumper talk he said that only with cam mod the bike was so easy to start even by hands. I will try and let you know. I agree with you, most people don't know how to start properly a 4 Stroke and ends up with disaster. So maybe this is one of the many reasons why the idler gear breaks up so easily. PS with restake the rivets what do you mean? To press the rivers more in? Sorry for my English. Thank you.
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