Finally about finished!

When I picked this bike up back in March, I didnt think I would need to do anything to it, as then engine was recently rebuilt, bottom and top ( even gave me the old parts ). Being new again to the 2 strokes, I wasnt up to speed on the whats good, and what to stay away from as far as parts. Anyways I bring it home and begin to look over it. I shined a light up into the exhaust port, and noticed a nice scrape on the intake side of the cylinder. Great, a new top end!! ( Ended up using a new oem cylinder and piston ) I tear it down. Someone told me to check the crank bearings while I was at it, and sure enough, play at the flywheel. Then I began to read how the wiseco cranks were trash. I knew I didnt have the funds to replace it, but didnt want to risk that crank. ( New oem 05-07 crank )  So I began buying a piece here, and a piece there ( After having to take even more time to buy the tools to do it myself, since I cant afford to pay someone to do it ). When it came time to start reassembly, I found other issues with other parts such as reeds, clutch cover, etc.....During this process, I kept telling my wife " All I need is this part or two, and that's it"....But I kept finding more issues, and needing more parts. By this time, she's about at her end with me, and believing nothing I'd tell her, as she's been hearing it the whole time.

     Recently I needed just a few small pieces, and one piece that was gonna take me sometime before I had the cash to spare for it. I sent a message to a fella on here, as I noticed he had changed out his stock clutch cover, so he'd possibly want to sell his oem one cheap, so it'd be within reach. After talking to him he wanted to send it to me free!! I hate to accept handouts, be a bum, etc...I really do. He insisted I take it, and asked if I needed anything else. Told him not really, but a few odd and ends bolts for the clutch cover. Needless to say when the parts arrived, I got way more than I could have hoped for. He sent me stuff that I didnt "need", but were surely better than what I had to work with. I made him a promise to do some pay it forwards, to help others when in need ( Which I have already done a few, and we're both strong believers in PIF ).  I'd like to take this time to thank " Gino208"...Thanks man, I wouldnt be where I am at right now, without your help . :thumbsup:  :worthy:


Now its wrapped up, and about ready to see if it all pays off, and if I done a great job. I cant help letting my mind race and I begin to have the "did I do this", "Did I do that" thoughts.  Pretty sure I did everything, as I took my time and paid close attention to torque specs, etc. But I still cant help but worry. Being ready to fire it off for the first time ( I will be doing this today ) I now got to worrying about breaking it in right. I been reading and researching, and just keep going in circles with all the info I found out. It's still as much of a mystery as it was before I searched, as there are a million different answers. Anyone have any advice that worked great for them when you rebuilt? Maybe a heat cycle or two on the stand ( Old bucket for me lol ), then an easy ride or two? I usually ran klotz, but I read castor 927 was great for break in, so I picked some of that up.

                      Well, here is what I have been working on for the past several months ( Feels like I started it in 2002 lol )   I'll get better pics today when and if I get it out )   Thanks again Gino!!





Edited by wykyd450r

Looks great hope to have one some day to tinker on I always warmed the engine up let it cool then rode it gently a couple times then changed the oil and let her rip and my cylinders always looked brand new when I rebuilt them I also ran the ratio of 32/1 for a tank or two buy then leaned that out a bit

Dude, that thing looks so sexy. It's a great feeling of accomplishment once it's all said and done. Also I can relate to the wife. I've only picked up a couple of things for mine so far. Yet the wifey is already ragging on me about spending money on "another frigging motorcycle". She does have a valid point though. This is cycle number 4 in the stable so I get it.

But seriously, your bike looks superb. Great job!!!!!!!!!!!!!

As far as break in goes for me. I'll start it up and let it get to operating temp and let it run for awhile without revving it up too high. Then shut it down and double check for leaks, everything tight and a quick look at the spark plug. Then I kick it over and rip it. Hope everything runs great for ya.

Edited by GustavMiller

March???? The riding season is almost over, go ride that thing!

Thanks GustavMiller for the compliments!! Much appreciated. Yeah, I understand her point too, as my hobbies come last, which is understandable. I just tore it down so fats with inspecting everything while doing so. Next thing ya know, I find this, and that so it took multiple orders.  I guess it seemed to her that all the money flying out, and it still dont run. At one point she said I was buying the stuff just because I had to have new. It was all the seals and bearings in the tranny so I wouldnt have to tear it down again ( Oh I hope not, for quite awhile ). Told her for 50-60 bucks I might as well while I was in there. She didnt see the logic lol.


Yep Monk....I know its about over now. I did make the comment to her that atleast I wouldnt have to rebuild it this winter. Still, didnt seem to impress her too much lol.



Going out in a few to mix the fuel, and see what's what. :(  Hopefully followed up with a :thumbsup:

Well, mixed the 927 at 32:1 and put er in. Kicked it softly 4 times to get everything moving. First real kick it lit off!! Smoked a bit though. I let it sit a few minutes raising and lowering the rpms to keep it running. Gave it a few small blips of throttle here and there. Tried to keep rpms varying. Figured I'd take it a few spins up and down our alley. Smoke seems to have cleared up alot. During the passes, I varied throttle and didnt let it get into powerband or anything. Now....I did notice when the rpms began to climb somewhat, I could hear a rattle or something along those lines. Is that what detonation sounds like? I couldnt really pinpoint where it was coming from. I remembered when I cleaned the carb, and the last owner had the needle on the top (1st) clip. I just now lowered it to the 2nd ( stock ). I am thinking there is a 370RD main, and a 32.5 pilot. Any ideas on this? I did also put new boyesen dual stage reeds in while building. New twin air filter oiled with PJ1 aerosol. Premium gas just bought and mixed this morning.  New piston/rings, cylinder, crank, everything oem....If it helps.


Also, how important is it to re torque the bolts after the first heat cycle? Some of those nuts seem to be hard to get to, unless I want to drain coolant and remove exhaust.




Atleast she runs.

Didn't get a chance to try it since lowering the clip position. I did have a look at the chain and it seems to be a little loose. I adjusted it and while doing so, I was trying to duplicate the sound I was hearing. I ended up slapping the chain off of the new all balls lower roller and the sound it made just might be what I was hearing. Maybe I can find out later today.

Edited by wykyd450r


Edited by wykyd450r

I did have a look at the chain and it seems to be a little loose. I adjusted it and while doing so, I was trying to duplicate the sound I was hearing. I ended up slapping the chain off of the new all balls lower roller and the sound it made just might be what I was hearing. Maybe I can find out later today.


That chain slapping sound always freaks me out. I always think about a crankshaft bearing when I hear it. If the chain is somewhat loose, it will want to slap the top of the chain slide while at lower RPM. If you ride it around in the yard slowly, and look down at the chain, you can vary the RPM or load on the engine and get the chain to vibrate and slap the chain slider below it.

Came home from work a few days ago, and thought I'd try breaking it in a little more, and while doing so, try and locate the noise I been hearing. Without thinking I fired it up and took it slowly up the tram road. I decided to take it up an old back road up the mountain thats constantly a climb. I figured a nice steady load on it while keeping the rpm's varied would help break it in. Its a couple miles up, so I headed up. Got most way up, and turnt back a trail, but quickly remembered hunting season is in, so I better get back to the road. Got back out to the road and shut it off to inspect eveything, and admire my work lol . Coasted it all the way back to the tram road, to give it a little cool down. Coming back the tram road, I began to look for the noise. Still sounded engine related. Decided I'd try to record it on my phone, so I shoved the top of the phone in my mouth to hold it by biting down and pulled out. After about 3 gears, I let loose of the phone and it fell. Trying to look down to avoid running it over, I could only watch it for a second to avoid any wrecking. By the time I got turned around, I was a ways from it. I go, park the bike and look for it. Black phone case, black dirt trail, and not much daylight left. I look, and look. After a long search, I finally found it.  Then I go back to my bike, and decided I'd try to listen for the noise with no helmet. I lightly go through a few gears, and roll on the throttle ( when it seems to make the noise )and hear it again. This time, it sounds like its in the rear sprocket area. I do it a few more times, and with no helmet, I want to pinpoint it to the chain/rear sprocket rubbing the guard. By now, I am happy its not anything serious ( I still havent tried it since I think I fixed it ). I go pick up my helmet, and head home. Started out the tram road and it died, right now. Then I remembered I only put a small amount of gas ( Les than a gallon Im sure ) in it the other day to see if it was gonna run.....DUH!! Long push home....Glad it wasnt the few miles further I was out. :goofy:

Well atleast it wasnt something more serious

I do have a question, that maybe someone can help me with. After the last ride, I noticed some residue on the side of the cylinder where the new exhaust flange gasket was leaking. I took the exhaust off to inspect it. During this time, I shined a light up into the exhaust port just to look around. I noticed on the intake side, on the corners of the intake port openings, a streak on each side, that has me concerned. It wasnt scratches, and I could still see crosshatch, but it almost looked like wear marks maybe. Like strips of where the shine was worn off. Anyone happen to think maybe it was from me running it completely out of fuel? New oem cylinder, piston, rings, air filter ( oiled with pj1 )


Because of these marks, I built a leakdown tester, and fixed the exhaust leak. I pressurized it at 8psi ( piston at BDC ), and after 11mins45 seconds, it didnt move enough to notice, if it even moved at all. So, I guess it wasnt from the exhaust leak, since the marks are on the intake side?

Nice bike man and I can completely relate to what you just went through. I bought a 96 cr250 for $450 that was partially in pieces with bad main bearings and spray bombed black, it was sitting for a year and I ended up going through everything you just did. Stripped all the paint from it, rebuilt the motor, new pro x piston, jug was already replated so that was sweet, clutch, wisco basket and pro x inner hub, alot of internal motor parts that were missing/damaged sourced and replaced, plastics, graphics, wheel bearing, suspension rebuild and all the bearings, etc, etc. Fire her up for the first time and she is running great, did 3 heat cycles on the stand, take it for a boot and crap where is the machine gun sound coming from. Turns out the msr chain guide was so worn the chain was digging into the bolts and this was causing the machine gun sound....sweet simple fix.


So I'm looking the motor over after the first run and I notice I have a leak at the base gasket right where the crows foot linkage is for the power valve. It was pushing the moly 60 grease out of it right at the corner. Pull the jug and decked the surface of the base(lesson learned here since I never had it running everything is a mystery) and find out that it is sitting 1/16th low around the whole corner...shit motor needs to come apart and install a new case half. I figure hey since I have it apart again I'm going to pull the oem crank with a hot rods rod that has 100 hours on it out and change that too, it was still in spec with no issues but at this point I'm not taking it apart again for being a dumb ass.


I order a hot rods full crank kit with vertex seals and gaskets included, do the complete rebuild fire it up and boom, leaking gear oil into the crank. Jesus, I mean I was super careful and everything looked perfect. So I take it to a local shop at this point for second opinions, inspected right side seal and it was perfect so the only other thing it could be is center gasket, pulled motor apart for the third time and sure as shit its a bad center gasket. The small section of the gasket at the back of the crank area that the center gasket seals was basically cut a bit oblong so it did not seal in just a tiny spot because the gasket shot out from that area when it was all tighten up, there was about 2-3mm where it was case half to case half with no gasket. I can't really explain this well so I hope this makes sense lol, I did look at it when it was placed down during install and it looked like there were no issues.


So I get the shop to fix this on round 3 because my wife is just sick of my attitude at this point and is about to file for divorce which I really can't blame her after all the nights in the shop and ruined weekends due to issues after issues. Shop calls me to say it's good to go so I go get it, fire it up and I low and behold have a base gasket leak again but this time it is a really small pinhole leak right below the exhaust port. Tried to see if it would seal with a little more torque on the base bolts, tried to heat the gasket up after that by running the bike and the rad decides to blow on me, new billet china rads on her now but the leak remains. Now it's really bugging me that I had no clue what the shop did with the motor and it's bugging me even more because I notice that he has installed some bolts in the wrong places, who knows what else he did. I decide to say screw it and yanked the jug apart myself again, turns out he did not use any hondabond on the center gasket seams like did the other 2 rebuilds, I think my deck clearance is ever so slightly out now because of the mismatched case halfs but its barely noticable that you would think a gasket should have taken care of it.


Well I'm pissed now because it was pretty obvious that I used hondabond there before when the shop took it apart just for good measure and he just put the new base gasket on thinking thats all good without thinking to ask what the hondabond was there for. I went easy on him and just made them buy the parts I needed to fix this, new oem base gasket, used permatex high tack spray a gasket all over the gasket, used hondabond 4 at the seams, put it all back together, wait 2 days to fire(that killed me lol) and now I have 2 hours ride time with no issues at all. Whew that was alot of info lol, sorry bout that but I just wanted you to know your not alone man:) Just checked back at my emails and whats even more funny is that I bought mine on March/26 so yeah I can really relate. In the process I sold my other bike thinking I had this under control, these last few months have really sucked so I'm really happy to hear you had a good outcome with this. Oh yeah fwiw I am into mine for a good $3500 now if that makes you feel any lol.

Edited by kurtus

Wow!! Yep, seems you are right there with me lol. I hope it pays off in the long tun. I took my time and read up, and researched and double checked before each move on the engine. Its just taken so long I almost forget if I did this or that while building. I am sure I did, but the what ifs keep coming lol. Im sure after a few rides, I'll feel more at ease. As much as I like wrenching and tinkering with these, I think I am just ready to ride.....Oh, winter is coming quick lol.

Got about 1.5 hours on it so far, and it seems to be doing well. My only gripe is the tmx carb. I raised the main from 170 to 180, and lowered the clip from the 2nd groove, to the 3rd. Still stock pilot ( 32.5 ). Really seems rich on the pilot. I turned the screw out from 1-1/2 to 1-3/4 with no real change. Gonna try out to 2 next ride out. Just wants to load up  in lower rpm's, it seems. Misses and hesitates til you get it going, then it'll rip. REALLY wanting a pwk airstriker!! My son in law has a yz250, and he took this a ride and the first thing he said was " I know who's building my engine next time".....He said it'll spank his, and his runs great. You guys think a 30 pilot will help me out on the bottom? Anyone happen to have a 30 they'd want to part with? Local shop can get them, if I want to buy 10 of them.



Edited by wykyd450r

Cool story guys. Thats why i alsways go crazy with sealant solutions when mating cases and base gaskets. No i dont just use permatex. I want the gooey stuff.

Cool story guys. Thats why i alsways go crazy with sealant solutions when mating cases and base gaskets. No i dont just use permatex. I want the gooey stuff.

I figure if I take extra time to prep the mating surfaces ( IMO thats the best prevention of leaks ) and use a sealer on the critical and hard to replace gaskets, I shouldnt have to pull it apart for quite awhile. My daughter is suppose to upload a vid of my son in law riding it for me. I had him ride it to give me his opinion. Hope I can get it up here soon.

also, when changing hard to reach gaskets, use OEM. you can never go wrong with those. and even though its not sealant from the factiry., doesnt hurt to put some.

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