S3 Race Custom Modified EC250 Complete Rebuild

[Jakobi]

Hope it solves it for you F5.

Things went reasonably well this arv. Wasted time putting the water pump cover back on. Had to come back off to access the front engine mount. Needed a deep socket to do up the lower engine mount too. A second set of hands would have been great for this too. Swingarm pivots lubed and slipped in easily. I had some dramas with the water inlet on the head. Over torqued using the torque wrench to specified reading but ended up crushing the gasket in one side where it wouldn't click (so technically didn't over torque, but too much for the thick gasket). Have some spares so slid in a thinner one and then had to change out the bolts for shorter ones as they'd bottom in the head before torquing down on the fitting. Then finally got there, hooked up the hose lines and then filled with coolant only to notice a pretty steady leak coming from this area. Not sure if I've got another bad gasket or an issue with the hose. Will investigate more tomorrow.

[GMP]

Not much on those M6 bolts, 6Nm. Needed shorter bolts? I've used ThreeBond on spigots and never had an issue, but Ahh, you have the S3 head.

[Jakobi]

Yeah the S3 head. I'll just snug them up by hand tomorrow. I've got 4 more of those litte gaskets in my spares kit too. No real issue.

[Jakobi]

One more thing Glenn, while talking torque values. I followed the workshop manual and that said 40Nm on both the pri drive crank nut, and the clutch hub, with loctite. Just checked my Yamaha manual and in comparison it asks for 75Nm on the clutch and 110Nm on pri drive nut. Thats a pretty massive difference, and here I was worrying I may have overtorqued the pri drive with the electric impact the first time around.

So will it be ok with the 40Nm and loctite? Clutch is ok. Its got locking tabs, but don't want that pri drive coming undone. I assume it would have been torqued to 40Nm at the factory, and it was hard to rattle off.

Edit: I have a bad feeling I'll have to drop the oil and pull the RHS cover off her again.. At least the coolants already out.. Searched and 98Nm is what you suggest for the pri drive. Can I get away with 40Nm on the clutch? I think I'll have to buy another lock washer if I have to bend it back again, and that was a horrible job!

[Jakobi]

I swear I've done everything 3 times with this bike.

Oil dropped again, side cover off checked the torque on the pri drive. Its tight! I locked the gears and put some considerable effort into trying to snug it up and shes not going anywhere. Based on that I left the clutch as it was. Ended up back in there again after double questioning myself if everything was right. Doubt is a horrible thing! Bike is back together all but the brake pedal, seat and tank. I'll kick it in the guts tomorrow.

[Neil E.]

Jake,
A caution on the use of Loctite: If you recheck a locitited fastener and it moves a tiny bit from the extra torquing, the bond has been broken.

Correct torque is necessary so the fastener does it's job; the loctite is there to keep the fastener in place (holding it at the torque value).
Neil

[Jakobi]

Originally Posted by Neil E.

Jake,
A caution on the use of Loctite: If you recheck a locitited fastener and it moves a tiny bit from the extra torquing, the bond has been broken.

Correct torque is necessary so the fastener does it's job; the loctite is there to keep the fastener in place (holding it at the torque value).
Neil

Thanks Neil.

I don't think it even moved when I went to tighten it up more though. What I'll probably do is order another RHS gasket and just double check it when I do my next oil change.

Is there any issues with removing the pri drive nut while the rest of the engine is assembled?

What sort of a poxy workshop manual lists torque values that are so far out?

[Neil E.]

If the nut is "most of the way" to the correct torque and it's loctited, you are probably OK. If we take 110 NM x .74 = 81 ftlbs and you've got the nut at ~60 ftlbs, the primary gear will be held in place. The real problem occurs when there is no loctite and the nut spins out hitting the cases.

In your situation you should be able to do some riding and prove out all the other work, then later pull the cover and redo the primary nut. If you are worried don't hammer on the bike too much on the first ride. You'll likely do a few heat cycles and some easy riding anyway.

[Neil E.]

Primary gear nuts and clutch hub nuts have been done "on bike" many times, nothing to worry about there.

[Jakobi]

I've gone with your advice Neil. I had the bike so far reassembled that I couldn't bring myself to pull the side cover again for the 4th time. I'll give the bike a few hundred kms (maybe 3 easy rides) and then when it comes apart for the suspension service and revalve I'll have the pipe off anyway and subframe flipped so it'll be the perfect time to check the nut out again.

It took a few kicks to get the bike started up and it blew smoke like a chimney. Probably a combination of some overflow fuel from the lectron when lifting it off the stand, having the choke on, and extra assembly lube. Bike came up to temp really well. No coolant or oil leaks. Most noticable was the reduction in vibrations. Heaps better than it was! I didn't follow any particular break in method. Just rode it around under light loads or throttle for a bit until the upper rad was warm to touch and then cleared her throat a bit. Avoided any constant rpm and just tried to keep some load on the engine to help bed the rings in. Varied rpm up and down through the gears. The engine felt very willing to take the throttle and pulled clean from bottom to top. Ran some tight ST nearby which is mostly overgrown and good there too. Then to finish off took the young bloke for a couple of laps around the yard.

Next mission is to fit a new rear tyre and then decide if I want to upgrade the plastics to 2011 spec.