crank seals

[shortzt.15]

Okay so I'm new to this forum and new to 2 strokes, I've always owned 4, I'm looking at a 250r that has the esr 310 kit and works dual rate with rezzs ect. Any ways it needs crank seals how hard is this to do? Can I do it with out spliting the case? Any help and pictures would be nice
For mechanical knowledge I'm 15 and just rebuilt my 400ex top end

[sangheraent]

yes you can do it with the motor inside the bike. Just need to take apart the entire left side stator and flywheel and then take off the clutch and primary drive gears. getting the seals out might be tough but putting new ones in is fairly easy just remember to put them in at the correct depths.

I think the clutch side goes flush and the other side for 6mm. im not 100% certain on that check the service manual.

[zedicus00]

if your new to 2-strokes i wouldre-trouble shoot and verify that it really does need crank seals first. have you fired it up? can you do a leak down test?

[shortzt.15]

well heres the problem, first to correct myself it has the ct310 kit wich i heard is better, but they guy im looking at buying it from had a mechanic look at it and told him its the crank seals, the motor is torn down, he has the jug and both side covers off, im trading a decent 98 kx250 so i dont have much into it and even if the motor is junk i can put all the suspension on my 400ex

[265 sleeper]

If you want to go fast that 310 will spank that 400 all day .Would be better off rebuilding that r instead of robbing the suspension off of it. Tools you'll need are flywheel puller same as for a banshee blaster 250r maybe a few other bikes . 2 cresent wrenches .17mm socket for flywheel . 32mm socket for clutch basket . a normal metric socket set for the rest of the bolts. Must remove clutch basket to get to the gears on crank . Then screw in a screw into the seal to remove stator side seal . Then once you remove the Collier on clutch side you should be able to use a pick set the remove seal. Collier is behind the crank gears. Also use blue loctite on steel on aluminum and aluminum and aluminum . Red on steel on steel.. clean all parts that using loctite on with brake cleaner . Carb cleaner has a oily residue which brake cleaner does not. Good luck with the r they are hard to find now days .

[shortzt.15]

Okay thanks, but I think the crank needs replaced I can feel the slightest bit of end play, so ill just buy bearings and seals and rebuild the hole motor with new bearing and seals,

[265 sleeper]

Bearing kit on eBay cost like 60-80 bucks almost complete bearing seal kit . Doesn't come with mechanical seal for water pump. But does come with all bearings . I would also send the counter balancer off to a machine shop to put that bearing on for you should cost around 25 bucks . Crank just order a new one. Make sure its not a stroker crank and or stock crank. They look the same other than the stroker crank rod is machined on the big end on the bottom. Gasket kit 45 bucks .

[shortzt.15]

For $160 I can get the crank rebuilt with a hot rod, connecting rod, it will also be trued and welded, also is the counter shaft bearing just pressed on because in that case I have a press but do you need a crank case splitter, and a crank puller?

[265 sleeper]

That counter balancer pully should be done professionaly . It needs to be spot on yes you can just press it on but there is a process in order to do so. You must first heat the gear up to not scar the gear nor the shaft then press off the gear but before doing so you must mark the gear with the shaft. And line the marks up when pressing it back on who ever is doing your crank should be able to do your counter balancer.

[shortzt.15]

Okay thanks for the info, I plan on having Dave Moore racing do my crank I just looked and they will do the counter balance for $45

[destey]

while your at it :)

http://www.exriders.com/vbb/showthread.php?s=&threadid=266381

I had them do my whole bottom end and it looks really good