Sudden rough running

[JZ05220r]

I did check the float height and I was at 17mm. Took it for a quick run and still the same results as expected. I’m hoping the problem doesn’t have something to do with the top end, particularly the sealing of the piston rings as I have already confirmed proper kips function.

I also realize it might be a good idea to try a new jet block gasket before I tear it down. I realized that the jet block testing using compressed air in the pilot circuit only truly tests the three little circles integrated into the O-ring, but not the main part of the outside of the jet block o ring. Even if a new jet block o ring miraculously fixed it, I’m still going into the bottom end to take care of those leaks, hopefully with no mishaps.

[JZ05220r]

I jumped the gun and now I have the engine out and I just pressure tested it one more time outside the bike and I’m a little shocked to see it holding pressure much better than it was before. I did just rinse it brush and rinse again. It’s still wet. I pressurized it to five psi and after eight minutes I’m at 3 1/2 psi. Must’ve had an external leak on the pressure tester.

[Chuck78]

Personally before splitting the cases, I'd try degreasing and smearing some type of sealer on the leaking areas, ThreeBond 1184 or 1197 or whatever the standard Yamabond/Hondabond sealer it or perhaps better, ThreeBond 1207b which is like a fuel resistant RTV silicone.

Replace jet block gasket again, definitely.
Compression test the cylinder if you think you're low on compression???
The top end wear would be noticeable in the kicker effort, I'd think...as well as starting effort.

Don't give up, you've got a really nice bike there, that you know well... Do you ride your E-Series as much, or the H-Series more? A new Beta 200RR, XTrainer, YZ250X, or KX327X costs a whole lot more than conquering this issue and learning from the experience.

We're all learning from this diagnostics experience of yours, and we'll all be more the wiser by hhe end of it.

Keep at it! I'm guessing jet block gasket, but also definitely acknowledging that the case leaks aren't a good thing at all and are possibly contributing, but should be repaired regardless.

[ss109]

Well said, Chuck!

[JZ05220r]

Thanks for the motivating post Charlie. I’m so confused because the leaks at the crank seal are no longer detectable. I have a loss of 1.75 psi in 10 minutes. I started at 5 psi. I’m gonna go and just throw some three bond in those areas right now while I have it on the bench let that cure on its side. I may take care of the base gasket as well. while I’m at it.

Starts first kick with choke and no priming kicks.

I don’t ride the e series much at all. In fact it’s sitting in my basement and I have it listed on marketplace as a feeler at the moment.

[JZ05220r]

After some thought I’d like to go the route to cover up those leaky areas with something for now. I have the cylinder off to replace the base gasket. For further testing, what do you guys think I should use to cover those crank seal areas? I have loctite 290 which is a more liquified green wicking type of threadlocker that can be applied to fasteners that are already installed. Then I have threebond 1211 I can carefully pack around the outside of the seal.

[Chuck78]

That Loctite 290 sounds like a good product to use! I would clean those areas with a toothbrush and some solvent really well, try it out extensively with compressed air and maybe a heat gun, and then apply a little bit of that. Then on top of that once that has cured, some ThreeBond 1211.

[JZ05220r]

That Loctite 290 sounds like a good product to use! I would clean those areas with a toothbrush and some solvent really well, try it out extensively with compressed air and maybe a heat gun, and then apply a little bit of that. Then on top of that once that has cured, some ThreeBond 1211.

So apparently the Loctite 290 cures in the absence of air that’s not something I want floating around in that area potentially ending up on the shaft.

[SpruceItUp]

I have a tube of loctite 515. It never 'hardens' and is really viscous. Almost like a gel. I use it to seal up the seal on my KIPS shaft that exits the cylinder, as when I do a leak down test it doesn't seal perfectly, so I seal it off with that stuff to make sure the engine holds pressure. It seems to stay in place really well. It is kind of expensive though, I think a typical tube goes for 30 bucks, but I can normally find it on sale for like 15 bucks.

I also use it to seal my oil drain plug, as the PO of my E series must have stripped the drain plug and used a helicoil and did a pretty terrible job, as they ended up tapping at a slight angle, so the bolt doesnt sit perfectly flush with the case, causing a slight oil leak.

It's pretty neat stuff, unsure if it will work perfectly for your use case, but figured I'd mention it just so you know about it.

Oh, by the way, once I put it on the KIPS shaft I don't have to replace it. It seems to hold the seal until the shaft is removed from the cylinder, so it doesn't seem to have much issue staying in place.

[JZ05220r]

Thanks for that suggestion, interesting how that’s worked for you and the packing seal on the right side sub valve shaft.

I’m starting to second-guess using the loctite 290 as it’s very thin. I don’t want it to get through onto the bearing. I did carefully spray around the outside with contact cleaner to get rid of any oil. I noticed the contact cleaner worked 360 degrees around the whole outer edge so I know that Loctite 290 will do the same. I just don’t want it to go through to the bearing.

[billie_morini]

JZ,
I think you made a valuable observation about how contact cleaner traveled. Yes, Loctite 290, the Green Penetrating Threadlocker, has a very low viscosity and can find its way to places that it's not wanted. I use it the immobilized the tiny screws used to anchor the butterfly to the rotating shaft when rebuilding throttle bodies. I learned to use the smallest amount possible to wick into the screw and shaft threads. When first learning this, some of the excess Loctite 290 ran along the valve shaft into the throttle body shaft bushing . This glued the shaft so that the butterfly valve could not rotate. Another time, a small amount of Loctite 290 ran down the butterfly valve disk and glued the edge of the disk to the throat of the throttle body. In addition to being very careful with the applied Loctite 290 quantity and location placement, I actuate the moving parts by hand before the cure time has elapsed. I'll actuate the moving parts at 2, 4, and 6 hours.

[JZ05220r]

JZ,
I think you made a valuable observation about how contact cleaner traveled. Yes, Loctite 290, the Green Penetrating Threadlocker, has a very low viscosity and can find its way to places that it's not wanted. I use it the immobilized the tiny screws used to anchor the butterfly to the rotating shaft when rebuilding throttle bodies. I learned to use the smallest amount possible to wick into the screw and shaft threads. When first learning this, some of the excess Loctite 290 ran along the valve shaft into the throttle body shaft bushing . This glued the shaft so that the butterfly valve could not rotate. Another time, a small amount of Loctite 290 ran down the butterfly valve disk and glued the edge of the disk to the throat of the throttle body. In addition to being very careful with the applied Loctite 290 quantity and location placement, I actuate the moving parts by hand before the cure time has elapsed. I'll actuate the moving parts at 2, 4, and 6 hours.

Thanks for reinforcing my thoughts on using the loctite 290. Still not sure if I’m going to use it. If anything, I would just do the smallest drop, hopefully seeing that go all the way around the seal.

I watched a video on a loctite representative discussing the loctite 290, and he mentioned there was a lot of customers that used it for casting porosity. I immediately thought about the steel bearing retainer indents on the exterior of the case halves and thought this might be a really good alternative choice versus the typical JB weld.