• 2 Stroke Husqvarna Motorcycles Made In Italy - About 1989 to 2014
     WR = 2st Enduro & CR = 2st Cross

  • Hi everyone,

    As you all know, Coffee (Dean) passed away a couple of years ago. I am Dean's ex-wife's husband and happen to have spent my career in tech. Over the years, I occasionally helped Dean with various tech issues.

    When he passed, I worked with his kids to gather the necessary credentials to keep this site running. Since then (and for however long they worked with Coffee), Woodschick and Dirtdame have been maintaining the site and covering the costs. Without their hard work and financial support, CafeHusky would have been lost.

    Over the past couple of weeks, I’ve been working to migrate the site to a free cloud compute instance so that Woodschick and Dirtdame no longer have to fund it. At the same time, I’ve updated the site to a current version of XenForo (the discussion software it runs on). The previous version was outdated and no longer supported.

    Unfortunately, the new software version doesn’t support importing the old site’s styles, so for now, you’ll see the XenForo default style. This may change over time.

    Coffee didn’t document the work he did on the site, so I’ve been digging through the old setup to understand how everything was running. There may still be things I’ve missed. One known issue is that email functionality is not yet working on the new site, but I hope to resolve this over time.

    Thanks for your patience and support!

250-500cc Wr250 powerband racket?

R

R_Little

Husqvarna
Pro Class
My 04 WR250 has a noise problem! It may be powervalve related.

I run a PC pipe and both the TMX and PWK carbs

It pulls from idle quite nicely with big power into the mid range and is rather quiet.

Once it hits the upper mid it becomes super loud like the muffler fell off. Power falls off like it is running lean and the bike remains loud and kinda flat until I shut it down and decellerate for a while then it instantly becomes quiet like the silencer was snapped back on and the strong mid mid range power returns.

Hold it open for a while in a sand wash and it'll remain noisy and flat for quite a while. Kinda like pressure has to be bled off until it returns to normal. Short applications of WFO are fine and the bike hauls....only long WFO straights are a problem like pressure is building up. the change to good power is instant and you can really hear the DB's drop.

It is really like the silencer is being blown off the pipe but everything is tight and even a rubber gasket on the silencer joint does not make a difference.

oh, a fresh repack on the silencer makes no difference.

The PV's are clean.

any ideas......
 
Maybe you should try running one carb at a time :D

My buddies 07 WR250 is to loud too. Kinda the same thing. OK at idle but when he is on it it is loud especially for a 2 stroke.
 
any chance the header pipe is moving out at the exhaust port under full power ?f
might check your flywheel key also in case timing related? billf
 
Sounds like your power valve is sticking in the open position.

Mine did that - it was really loud and had no bottom end. After some time at low rpm the valve would close and the engine would return to normal until the valve stuck again. It took a very thorough cleaning to get it to run properly.
 
woodzi;97609 said:
Sounds like your power valve is sticking in the open position.

Mine did that - it was really loud and had no bottom end. After some time at low rpm the valve would close and the engine would return to normal until the valve stuck again. It took a very thorough cleaning to get it to run properly.
Click to expand...

That is exactly what is happening.

The problem is the PV is clean wit new bearings and everything.

I did have some wear on the side valve bushings so I'll look at that.

Thanks!
 
It sounds like you have already found your problem.

Just another thought for others that are noisy - my FMF Gnarly rattles around at a certain rpm. I've tried heaver springs, repositioning the pipe hangers. The only thing that stops the rattle is to have my buddy hold his boot on the pipe while I rev it. Too bad he can't run very fast on one foot...
 
Huh! I just realized that was what was happening to mine too. I thought the PV wasn't opening because there was no hit. But, now thinking about it, it was open the whole time. This from the last GNCC I did, which was a 3+hr race WFO. I cleaned the PV and fixed it....but I had technically diagnosed it backwards. Good info.
 
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