Air Cooled rebuild

CRMOE500 · Post by **CRMOE500** » October 11th, 2012, 3:49 pm

Finally after a few years of sitting in pieces I am rebuilding my 84. A good friend of mine got me motivated when he mentioned that his Dad used to race dirt bikes professionally back in the 70s and 80s for Honda. If you followed racing in Ontario Canada you may have heard of John Lake. He had the second 73 CR250 Elsinore in Canada and did very well through out his career.He has great stories and pics from back in the day which I will try and post up. John is also a licensed mechanic for just about everything so I'm glad to find someone with his ability.
After tearing down the engine he found the trans to be in great shape with next to no wear on the shifter dogs or gears. The cylinder was on it's last bore, so I opted to have it resleaved instead of chromed. Bike Works in Kitchener has a great machine shop and did the machine work. John replaced all the bearings, making the job look easy. The crank I had gotten from DaHonda or whoever it was with "5hrs" on it turned out to be a paper weight waiting to explode. So john rebuilt my old one with a new rod from Honda. We now have the bike back together, but now we need a carb cuz the main jet fell apart. I figure on getting a PJ Mikuni soon as I can find one, along with a new kickstarter. Sorry I don't have any pics right now, but they are coming.

CRMOE500 · Post by **CRMOE500** » October 13th, 2012, 12:54 pm

So here are a couple pics that I do have. In these pics john has just finished installing the bearings and crank along with the trans gears. Since I've never worked on one of these before and wanting it done right with no mistakes, I was glad to have Johns old school ability in putting this together. He made it look easy bolting the cases together with no hangups and a smooth shifting tranny. By next week I will have a carb and this bad boy will run. Bob's break in procedure will be next and soon I will post the results.

Post by **AlisoBob** » October 13th, 2012, 1:56 pm

Nice job....

CRMOE500 · Post by **CRMOE500** » October 13th, 2012, 3:01 pm

Thanx Bob. I debated on posting this pic because of it's poor quality, but here it is. John was impressed with the machine work, I was relieved because I have close to 8 bills into the cylinder alone. Poor machine will ruin your day, but the boys did a nice job with the bore fitting the new Wiseco perfectly.

http://www.youtube.com/user/500bigbore · Post by **Roostius_Maximus** » October 13th, 2012, 8:22 pm

Could have slipped a newer shaft set into that motor while it was apart, could be running the 1986-01 clutch bearing and the 1988-13 sprocket spline.

CRMOE500 · Post by **CRMOE500** » October 15th, 2012, 3:42 pm

Your right Roost, that upgrade would have been ideal had I known. I'm guessing that would have meant newer clutch basket and plates to match. The basket and plates that I have look really good, so maybe after there done I'll make the upgrade.

http://www.youtube.com/user/500bigbore · Post by **Roostius_Maximus** » October 15th, 2012, 5:16 pm

the basket would only need the center pushed out and the 1986+ one pushed in. The inner hub can be used either way. If you get to where you want to use a new style billet basket I can cut one down too. I'd used a vortex basket in a stock 1988 500 before, the basket was a billet from a 1999 cr250. Fit with a trim to the baskets oil flange on the outside.
If you ever get into it again I likely have everything

CRMOE500 · Post by **CRMOE500** » November 21st, 2012, 5:08 pm

So after a ton of hard work from John with my help, Roosty who sent me a great PJ carb and still not accepting requests to send money, my Finner is running awesome. I went over the carb, John checked the float level and in 6 decent kicks the Finned Monster roared to life. It has never started easier, and revs smoothly with next to no vibration at all. Tomorrow I will install the chain, hook up the brakes, and get this beast moving.

http://www.youtube.com/user/500bigbore · November 22nd, 2012, 4:32 am

Sweet!

sabreguy · Post by **sabreguy** » November 22nd, 2012, 5:50 am

Now post some pics

Tharrell · Post by **Tharrell** » November 23rd, 2012, 2:10 am

sabreguy wrote:

Now post some pics

Vids would be great too.

CRMOE500 · Post by **CRMOE500** » November 25th, 2012, 3:27 pm

Put together the rear brake rod I made to replace the old one, hooked up the chain fired the beast up. The empty lot beside John's shop was only big enough to get in second gear power band before having to slow down. Soon as the power turned on the front end lifted in the same manner with scary ease. I have tomorrow off from work, so I plan on taking the bike to my friends farm and start breaking her in. And yes I will try and post up some pics.

CRMOE500 · Post by **CRMOE500** » November 26th, 2012, 3:16 pm

Well I dd get her out today, but I was unable to get a way to get the bike to my friends. So I had to make do with a few banzai runs up the street just to check the trans, which worked flawlessly. Being that it's -2 I used a hair dryer to warm up the motor, which still needed 6 or 7 good kicks to start. The carb leaked fuel, so I readjusted the float level, stopped the leak, and it ran great.On my next try I loaded the motor up with fuel and spent the next 5 minutes kicking it all out before it would start again. Oh well it is Monday, so I'm happy with how things worked out. There is still a lot of work to do, like fix the throttle which is now to long, rebuild the suspension, and reseal the pipe to the head, but all in good time.

BannedCR500Riders.com

Air Cooled rebuild

Air Cooled rebuild