Fixing problems with new (old) bike. - Running

[Gage]

Ok guys... So I decided to put the crank in the hands of somebody who knows press together cranks, and hasn't played a continually losing game the whole way. He managed to get it straight to within .0025 or so on one side and .0015 on the other. That'll get the job done. I took it home and went to a friends house with a hydraulic press and pressed it right in without a hitch. On advice from the machinist, I fashioned some aluminum wedges to lightly tap between the crank webs on each side of the rod, put cardboard over the rails of the press to set the cases on, and pressed it right in. IMO the force required never came close to harming the cases or the bearings, and everything went together fine this time. So much so that I regret having tried any other way.

On a more familiar note though, I managed to break my new shifter shaft, and waste my brand new clutch nut and gasket as well. It turns out the stud that guides the shift shaft was not all the way down either, and when I (cautiously) tightened the cover down, I noticed that the shift shaft wouldn't shift. On investigation, it turns out that the stud held the pawl up, bending it. Attempting to straighten it resulted in it cracking. It turns out to be hard coated or nitrided or something. As I tried to bend it with pliers, the surface cracked and flaked like glass... Definitely scrapped now. So, in short, I spent 3 hours to trash 100 bucks in parts, and ends up worse off than I started, which now appears to be customary when working on a KX500.

Man that sucks...

[MeanGreenMachine]

Well... The bike is running. Though I have seemingly endless reasons to be paranoid, I think that things are going to work out ok after all.

I thought about having the crank torn down and reassembled, or buying a new assembly and sending it out to be balanced and welded, but at this point, so over budget, the choice was pretty clear: get it together and ride this thing before the growing resentment and unending money pit ends up talking me out of the bike.

That said, at .0015-.0025 misalignment, if you think about it, it's likely that even kicking the engine over will cause the crank to deflect by that amount. All that vibration shaking a 230 lb bike around? It's being transmitted through those 2 bearings. Sure, I expect that it's lifespan will be effected, but I'm hoping to get my fill of good riding out of it before having to crack it open again.

Anyways, after I finished putting it together, I turned the gas on, held the kill button and gave it 2 kicks, and sure enough, it started on the very first kick once I released the button. The bike even idles now once warmed up - something it wouldn't do before no matter what I did. I let it warm up for 5 minutes or so until the rads heated up and carefully rode it around the neighborhood for 15 min the next couple of nights. Finally last night I took the bike out to the dirt after work and after riding around enough to be at full temp opened her all the way up - insane! Instant wheel spin and fishtailing unless I sat back off the tank some, and then, instant wheelies. I'm pretty sure that the KIPS is working right, as you can really feel it wake up and go apes**t once you're in the upper rev range.

[Pmcg]

Good to hear you got it running. You'll be an expert for the next rebuild.

[MeanGreenMachine]

Hey guys, been awhile so I figure that I'd report in now that the bike has been running for awhile. The power is even more amazing than I remember when first riding this bike, and so far, all of the gear whine rattling/rolling bearing noises haven't gotten louder or resulted in the engine exploding - so far.

The first thing I noticed is that it was eye watering, smoky rich off idle (55 pilot, needle 2nd clip), but cleans up after 1/3 throttle up to WOT fine (168 main). I'm at about 1000 ft., Weather has been around 60 degrees. The engine is stock, with a FMF Gnarly pipe and Turbine Core in bad need of repacking. O ring seal at the cylinder is nearly perfect due to slightly oversize O rings for a tight fit, new springs, and copper gasket. I eventually reduced the pilot to 52 with the needle at 2nd clip and it cleans up just off idle but the plug still comes out black and wet if I haven't hit WOT. I'm debating on whether to go further or leave it avoid potentially seizing the piston coming off WOT. Perhaps slightly richer on the main and slightly leaner on the pilot would be safer? I ride almost primarily in the desert.

Other shakedown problems include slowly weeping coolant from the head gasket on each side when the bike gets hot enough, and a slightly damp look with dirt collecting around the base gasket on the sides - it may be leaking. I know that I had to helicoil a couple head studs and one was sort of borderline when I put the head on. I may end up pulling the head and cylinder to inspect, helicoil head stud threads, and re gasket with Cometic gaskets or the like. It's got a factory base gasket and whatever paper with steel ring type head gasket came with the Wiseco piston kit.

[Pmcg]

From what I read on this site those in the know recommend countersinking the head studs to make sure nothing gets pulled up. I countersunk mine just a bit might not be a bad idea if you take it back off anyway

[MeanGreenMachine]

I think that US Chrome (or the previous owner) actually countersunk the stud holes. The top surface was lapped flat and everything, too. It's still possible that they pulled up, and it's possible that the one stud (and possibly others) that had weak threads decided to creep. I will probably pull the head and jug and helicoil the rest of the head stud holes on the mill just to be sure, counter sink again, and replace base and head gasket.

Anybody have recommendations for head and base gaskets? Cometic? OEM? I used an OEM base gasket but it looks like it may be leaking a tiny bit/collecting dirt. Maybe not, but the talk of sucking base gaskets scares me, so I want to put the best in while I can.

I was running the Wiseco HG that came with the top end kit, but it's not really top quality. It's a bit thicker than the steel gasket that came out - I'm trying to avoid having to mix in race gas and stick with CA 91 if at all possible. I don't need max power, just max reliability since it's going to be a desert bike used far from home.