I'm thinking about the things I need to do to keep riding safely in remote areas. One of these is a kickstarter in case the battery gets drained (I laid my bike down in rocks and flooded it, my riding buddy was real worried it wouldn't start before the battery died - happy ending though ).

Two thoughts keep going through my mind:

1. spare gas (easy fix with bottles or bags)
2. kickstarter mod

When I read up on the kickstarter modification, I keep reading about an ACR modification because the KLX-250S has the old KLX-300 ACR which is weak and can break with a kickstarter. This also leads into frequent discussions about the idler gear being weak (thin with weak heat treat). The idler gear fix using a modern KLX-300 gear seems pretty easy but, the ACR mod is still a little bit of a mystery to me. Should I just take the cam out and send it to someone like "brewster" (from ThumperTalk) and then reinstall it?

Is all of this overkill? I should note that I'm thinking seriously hard about a Mikuni pumper carb and a Bill Blue 351 upgrade this summer so, I need to be able to kickstart the larger displacement motor.

Thanks!

 

you could allways pop start if the batt dies.....easier with a buddy,just bring a short rope,rode all day with a guy that had a bad batt.we just pulled him to start up...

 

I heard my name (Brewster) mentioned so I came here to see what it was about. I hope I can clear up your concerns.

I would be surprised if the 250S ACR is timed the same way as the pre-2002 KLX300 and KLX250. Kawi changed the ACR timing mid 2002 on the KLX300 to the "easy kick" position . The ACR doesn't break. It is the bushing in the idler gear that gets sloppy, causing it to wobble and contact the clutch cage, causing damage. The "easy kick" timed ACR bleeds off more of the compression pressure when kicking the engine over. That reduces the forces on the idler gear.

Ride on
Brewster

 

Hey, this a first. Good to see you pay us a visit, Brewster! Yes, the exhaust cam PN on the KLX250S is the same PN as the pre 2002 KLX300.

Sid, it's just like Brewster said. The idle gear has not changed. The ACR timing was changed to relieve pressure on the idle when kicking it over. It also improved starting to a 1 - 2 kick affair.

 

Tremor38 is right! I just looked up the part numbers on the Kawi site. I thought that the Kawi engineers would have learned a lesson with the KLX300.

Ride on
Brewster

 

Brewster THANKS for stopping in to educate me!

If I take my motorcycle into the dealer to for it's next service interval, is the retimed ACR something they can do without too much trouble? Should I just take it apart myself and send it off to be retimed?

For that bushing on the idler gear, should I just check it periodically or do I need to replace some parts to make it more reliable?

 

That doesn't work so well in sand or in rocks. I went from the rocky ledges with loose rocks to really bad washed out places in the road that were 2 feet deep and 1 foot wide for hundreds of yards with half buried rocks the size of a bowling ball to keep things interesting. There was no way I could push start (or pull start with a buddy) in that terrain.

 

So y'all are saying that if you install the kickstart kit, you run the risk of breaking the ACR stuff inside like on the older bikes? That sounds lame, and all the more reason I'm glad its only electric start...

 

Most dealers won't have a clue about the ACR timing mod. I've done about 110 of the ACR mods so far. All I ask for is enough $$ for a sixpack of good microbrewed beer and return postage.
There is a writeup about the mod here:
http://www.planetklx.org/techtips/acr.html

Check the idler gear at the same intervals as your valves. It will become wobbly on the shaft.............measurements?, I don't have a guess of an answer. The bushing is splash lubricated so it can't be too tight.

Ride on
Brewster

 

The dealer will be clueless. The only thing they can do is sell you the very expensive newer cam for the KLX300 and they might even argue with you on that.

The re-time is kinda touchy unless you've done it before and it's really easy to break-off the ears that the timing sprocket mounts to if you don't have the right fixture (It's done with a press).

My recommendation is to send your cam to Brewster. He is veteran with the re-time and does it for dirt cheap.

As far as checking the idle gear, yeah good idea, but your bike doesn't have an idle gear right now. There is a place for it, but you install that with the kickstarter kit. (apologies in advance if you already know that )