• 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 The previous version was outdated and no longer supported.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 94 WXC-250 rebuild / help

Motosportz

Motosportz

CH Sponsor
Staff member
Most of you know i picked up a nice 94 WXC-250 for $300 bucks the other day.

http://www.cafehusky.com/forums/showthread.php?t=5000

Was told it was seized but when I got it the motor was free. As i cleaned the bike up I kept running that kick starter with my hand and it seemed fine. Long story short it fired up ran good. Rode it 180 miles on hard core trails and a mile from the truck the last day it seized... again.

So I ordered some parts and tore it down. The bike still kicked over EZ but i did find the piston stuck pretty hard. Anyway looking at it I'm thinking it needs the full rebore / plate oversized piston gig. I was hoping to clean up the cylinder and ride it this weekend. Not sure that is going to happen.

Anyone with experience with these things fee free to chime in. I'm going to take it over to engine guru Russ Fletcher today and get his opinion. Ether way I'm really looking forward to riding this bike rebuilt and with the new Boysene reeds. The thing ripped with a seized piston, it's going to RIP with a new piston and performance reeds. wooohoooo.

BTW, the plug look lean so i will richen up the jetting before i fire her up again. Someone replaced the Mikuni with a Keihn

Maybe the aluminum on the barrel can be lightly honed off? (wishful thinking?)

659620487_7teRR-L.jpg


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Super simple PV system...

659620369_kHRtv-L.jpg


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There's only 1 way to find out:)
Get a diamond hone on that baby and see if she cleans up and how round she is.

If it cleans up then you're golden.
And if not, then it's another $200 for a strip and re-nik job. You're still ahead of the game :thumbsup:

Looks like it wasn't warmed up properly before getting hammered on....once upon a time. Maybe that's why it tossed the old owner :D
 
Motosportz;50824 said:
Several people tell me to clean the aluminum off with muriatic acid and slap it back together. :excuseme:
Click to expand...

I've read that before too, but never tried it. I'd be nervous using acid on the coating.

I melted a piston once and took the jug to guy in Milwaukee with a diamond hone. He cleaned the cylinder up perfectly in about 5 seconds and it looked about the same as yours does. Didn't even charge me since I bought some rings from him.
 
Just got off the phone with guru Russ and he says do not use muriatic acid. He said it can work but you have to be SUPER careful and it is a crap shoot. he said it will not hurt the coating but if you touch any exposed aluminum it will eat holes. He also said it makes everything in your shop rust after you open the bottle. He said sand it off. Also was not big on the diamond ball hone, says it chamfers the ports, leaves the cylinder out of round and is just not the right application. Good old fashion elbow grease and sand paper is the way to go.

I also ask him about plating and he said he has been doing steel sleeves instead. He can bore them perfectly round and true. His experience replating cylinders is they end up out of tolerance, not round, not true top to bottom and just not good overall.

so I am going to try and sand it off. If not Russ will be putting a liner in it.
 
I talked to Eric Gorr for a while and he said it's best to start fresh, whatever the method. He's got quite the package deal as well.
* Cleaning and disassembly
* Inspection and measurement
* Over-boring
* Porting
* Replating
* Diamond honing
* Head mods
* Powervalve service
* Piston and gasket kits.
all for about 500 is what he quoted me for my 01. I'm sure it would be less if you already have piston/gaskets.
That is to put it back to stock, it's more for the 275 kit.
 
Kelly,

Muriatic acid(Hydrochloric acid) is doable if you have a steel liner but is very easy to screw up. We used to use it on Ski Doo's back in the early 70's when they had the high speed jet adjustment in the riders lap where he could try for the extra little bit of power that caused a zillion problems and they wanted it running again that day with no cost.:excuseme:

I would definitely start fresh and a steel liner is a nice solution. It is not like these husky 2 strokes run hot and you have to have immediate heat transfer.

That is the same PV setup as the WR 360, very simple and effective. I switched my 360 to the boyesen 2 stage reeds for the 360 and with the conversion to the PWK made a huge difference in low end response time and ease of jetting.

The only thing you need to be aware of is your current carb has an intake end spigot that is about 2 or 3 mm larger than the 38mm pwk airstriker. You need to either make a bushing or if your intake boot is still supple it has enough give to be able to just tighten it done the extra bit on the pwk spigot. I have been running my 360 this way for 2 years with no issues. Also check your intake boot/reed valve cage alignment. This was an area I achieved huge gains by matching these areas up and removing the copious amounts of extra material.

Keep us informed as you make progress,
Walt
 
I did what Russ said and sanded it with 300 wet. Got it off and the cylinder looks good. not perfect but good. I'm going to slap it back together and run it. If I ever have a failure I'll sleeve it. i think it will be fine. will snap some pix.
 
Motosportz;50824 said:
Several people tell me to clean the aluminum off with muriatic acid and slap it back together. :excuseme:
Click to expand...

Done this many times back in the day with great success. Use a "Q-tip" and just smear it on the aluminum in the bore, of course.
 
Motosportz;50875 said:
I did what Russ said and sanded it with 300 wet. Got it off and the cylinder looks good. not perfect but good. I'm going to slap it back together and run it. If I ever have a failure I'll sleeve it. i think it will be fine. will snap some pix.
Click to expand...

Good deal!

Hey Kel,...I know you've been riding a long time and you know your way around bikes, and I don't mean to be preachy or anything. But I've been riding two strokes for about 35 years myself, and Robertaccio and Ajax are straight up right on this one. When you wind a 2-stroke out to the moon and then chop the throttle you're not only robbing the piston and cylinder walls of lubrication,...but you're also robbing them of the cooling effect of the atomized fuel mixture as well,...and at the absolute worst possible time too. Seriously man, don't do that. Pull in the clutch and blip the throttle a few times, and use the brakes,...or do the Ajax kill switch method and at least take the fire out of the equation.
 
Rusty 2;50929 said:
Good deal!

Hey Kel,...I know you've been riding a long time and you know your way around bikes, and I don't mean to be preachy or anything. But I've been riding two strokes for about 35 years myself, and Robertaccio and Ajax are straight up right on this one. When you wind a 2-stroke out to the moon and then chop the throttle you're not only robbing the piston and cylinder walls of lubrication,...but you're also robbing them of the cooling effect of the atomized fuel mixture as well,...and at the absolute worst possible time too. Seriously man, don't do that. Pull in the clutch and blip the throttle a few times, and use the brakes,...or do the Ajax kill switch method and at least take the fire out of the equation.
Click to expand...

I have NEVER had that issue in 30 plus years of riding. Weird. Several friends who read that post said the same thing "never heard of that?" Also this bike was siezed when i got it I just did not believe it. I also believe the carb is way lean (someone replaced the Mikuni with a Keihn) and the plus was white. I will heed your warning but have never experienced this issue.

will richen the carb before riding again.

Here is how she turned out. Have not started it yet but lots of compression.

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Gosh that sure looks good to me,...looks like brand new almost. You're the fastest top-end wrench I've ever seen!

And,...I of course have no way of knowing that the high speed chop is solely responsible for causing that bike to sieze this particular time. I'd be a fool to presume that from 3000 miles away. I'm just sayin' as a general rule,...that ain't good for 'em. You can see the reasoning why,...right?
 
Rusty 2;50974 said:
You're the fastest top-end wrench I've ever seen!
Click to expand...

Been wrenching for 30 plus years. 2 strokes are super EZ. I had originally planned to have this done in about 3 hours and ride it the next day but the aluminum stuck tot he cylinder had me evaluating my situation. It turned out good and should be fine. I may sleeve it some time down the road / next rebuild.

I hear you on the high speed / chop the throttle thing. Will remember that one. It's also getting a bigger main. Going to ride it tonight.
 
jmetteer;50973 said:
Pistons in backwards... :banghead:

No you didn't, I have rebuilt enough to know as i learned the hard way on a 76 YZ125 back in the day.

made ya look!!! :D


Later,
Click to expand...


No you didn't, I have rebuilt enough to know as i learned the hard way on a 76 YZ125 back in the day.
 
BTW the powervalve system on this bike is super simple to disassemble and work on. Nice. It also has adjustable stops for full open and close. It's a cool and simple design.
 
good job!! the cyl looks great,
PS I was referring to that motor regime, the throttle chop from hi rpms, that it is a critical place for good jetting. I have never used any special methods while riding (like others do) , just have the jetting dialed in properly.
 
So I just looked the jetting over and it seems very close to what my bud is running on his 07 with a Keihn.

What I had in mine (none air striker, plain old Keihn PJ with the turn the choke to set the idels model)

55 pilot
168 main
G needle in the leanest position.

As I hear some pinging and this motor had been seized once before I'm guessing the needle was to lean all along. So I moved it to the richer middle position and put a 172 main in. We will see. If anything i will be slightly rich now but that's OK on a new motor especially.

Looks close jetting wise here as well but they are running a 65 pilot.

http://www.carbparts.com/keihin/pj_jetting_and_dimensions.htm

Dimensions for the G needle (seems like the middle of the road needle)

http://www.carbparts.com/keihin/needles_tuning/jet_needles/pj_34_39_jn.html
 
just a reminder Keihin and Mikuni use different measurements for jet size. I think that Sudco has a chart for X ref. Again great job on the cyl clean up looks really good.

subject change, just walked around the pits at the speed fest here at NAS NI , wow some real super classic race cars here (again). The ferrari 312,,was my fave of the day with the 917 porsche turbo (mark donohue car) next, love those GT (P) cars open and close cockpit types.
 
Kelly,

Nice job:thumbsup: That PJ will still be better than the TM that came on the bike stock.

PS, we still need picks and reports on your WR 125 suspension. I am really interested in what your friend thought of the power potential of the 125. It is official end of season here(hunting season) and time to muck about with your bikes.
 
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