Well I managed to swap flywheels without screwing it up

I thought I'd read where one guy here saved something like 1.4 lbs and cpr1 said he'd taken off "about a pound" but the difference comes in at exactly 240 grams lighter than stock-or just over half a pound. Still, a nice chunk not to have to be accelerating.

The local machinist had offered to take a little more off the big OD a few months ago but I left it as I got it from the US.

My anti-torque gear thingy bushing in the case was in perfect shape, so no probs there. When I was done it started up with no funny noises and there's no left over parts so ... so far so good.

The tool I used was just a long piece of steel..looking a lot like a lawn mower blade with 3 holes at one end. One large hole for the socket to go through and the two adjacent holes were for two 9/16 bolts with their heads cut off and those ends turned down to 11mm I think it was to form a little shoulder as they went into the holes that are in the flywheel.

If anyone wants I can post a pic of the cheapo tool later. I used a bolt I'd bought cheap instead of my rear axle to screw into the flywheel-which didn't budge at first, but a little heat and it eased off nicely.


I'll test ride it tomorrow and hopefully have something to report back. But it'll be hard to tell unless it's trying to flip me over backwards because anymore this things just all power anyway.

I was going to wait until I got accustomed to the change in power the air box holes seemed to have unleashed before swapping flywheels, but I don't know if there is any getting used to the newfound power. At least not on the street. The higher gears seem to pull just as hard as the lower gears ... at least with 14/48 gearing..


- The last car I owned in the USA before moving here to the Philippines was good for 11.8x on drag radials btw

 

OH, hold off on the MCM... I don't think your 07 needs/improves with the MCM. Check the thread. It also seems that the 08's and down have more HP than the newer bikes.

 

The problem with a lightened flywheel, is that if you take of TOO much, it becomes really easy to stall since there is less reciprocating mass.

For example if you could let the clutch out in 1st gear and idle over baseball sizes rocks, that same activity will stall your engine. You could either gear down even further, or of course play the clutch a little bit.

 

The 250 might spin up to speed a milli second faster, but off road plonking around will be more of a challenge. Definite low rpm stall mod

 

hopefully ill have my flywheel back next week.

also, not everyone off roads these bikes guys ;-) if im stalling out on basktball sized rocks, then i took a very wrong turn.

 

Yeah, I don't think I'd want this mod on my KLX the way I use it, but I'd bet it would perform quite well on the motard model.

 

I'll probably wait the two months or more until my a/f meter etc arrives before I do the MCM, just to not have to kind of stumble around with jetting guesses while doing WOT plug chops etc.

Maybe the newer ones respond better only because their FI senses the required jetting change and compensates automatically, then it'd be interesting to see how my f/a changes after doing that mod.

It's easily reversible after all if I just take the spring off the ACR


This bike was an SF before the US had that model, and I have the XR200 for off-road anyway. I won't be doing any rock jumping either

 

None of the newer 09+ are Fuel injected in the states. That is not why it works better on those compared to the 06-07. I'm not sure what the reason is.

 

I took the flywheel completely off one bike years ago running total loss just to see how it felt...maybe an XT500, and the acceleration difference SOTP was profound-like a 2 stroke


It'd be nice if RayCour, the guy that made the CDI unit for the KLX a few years ago, could put his efforts into a internal rotor CDI that weighed next to nothing and would still power lights, charge the battery

 

Right you are...well I'll give it a try someday just to see