Lugging the WR450

I have always favored 4-strokes because I like riding tight woods and always found the low end torque to be an asset. I have noticed however on the WR that when I'm in the real slow stuff that lugging the engine in 2nd and sometimes 1st the bottom end makes some discouraging noises, knocking mostly. How much damage does lugging the motor cause?

Also, I have disconnected the gray wire. Will re-connecting it give it back some low end grunt?

When mine makes a racket while lugging it, it means it's time to tighten the chain.

Try a 48 pilot jet. Mine had much better bottom power with the 48 than the stock 45.(w/stock needle)

Yes, ability to lug in normally associated with any 4 stroke, but ther exception is any with high comression ratio. The WR rolls a 12.5:1, this makes going over a compression stoke a little more violent as slow speeds and that "impacting" or rattle is the gearbox and everything else rattling. Its creating lots of wear, so spin er up a little more. Only other oprion is to stack about a dozen headgaskets on it, drop it to about 8.5:1 and lug er all day, of course, power will come up missing. <OK, dont really try this lower compression trick, though, it will probably work> ;D

No real damage I do it all the time and ride more in one year then most do in 3 years. The motor can handle it dont worry about the "tank-tank-tank" noise you may get when lugging under load. Fantastic motor! :)

Gear it down a tad!!!

Thanks for all of the responses. I am running a 48 pilot with the fuel screw adjusted to best performance depending on the weather conditions. My gearing is at 13/50, I have considered putting a 52 on the rear. As far as lowering the compression, if I wanted old technology I would have bought an XR400 for crying out loud :):D I guess my riding skill just has'nt evolved as fast as the 4-strokes have!!

I think it's mostly chain slap. I noticed same thing when I first started riding mine. I ride a lot of tight woods and technical stuff. For me the 52 rear sprocket really makes a difference. :)

I also would like to know if reconnecting the grey wire will give the 03WR450 better low end. Anyone know? :)

When I lug my 400 I just assumed that the noise I'm hearing is the piston rocking in the cylinder since the pistons are so short. The sound is light, not heavy like gears or chain slap.

13/52?? #$%@&*! ????? Must be a torque monster. I thought my 14/50 was low enough.

Hamish

when I'm in the real slow stuff that lugging the engine in 2nd and sometimes 1st the bottom end makes some discouraging noises, knocking mostly.

Check out Motomans advise on fixing the swing arm slider.

http://motoman393.thumpertalk.com/

Did it to mine and all of those nasty noises at chugging speeds are gone. I used a piece of neopreme foam with a peel off adhesive on one side. Ski shops usually stock it. You won't beleive the difference, 10 minute project. :)

Check out Motomans advise on fixing the swing arm slider.

http://motoman393.thumpertalk.com/

Did it to mine and all of those nasty noises at chugging speeds are gone. I used a piece of neopreme foam with a peel off adhesive on one side. Ski shops usually stock it. You won't beleive the difference, 10 minute project. :)

Can I get an AMEN :D

This mod has fixed more funny noises described by bunches of different guys. It's pretty funny actually. :D

Amen! :):D :D

I had asked about the chain slap noise here before, I usually hear that when taking off from idle. The noise I'm hearing on tight trails appears to be coming from the lower right side of the motor. I do plan to make the chain slider mod as soon as I can and hope that makes the noise go away. Thanks.

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