Top end rebuild

Hope this is on subject. If I remove my cylinder for leaking base gasket repair will I need to hone the cylinder upon reassembly?
jefft
 
sivarTi, get the complete engine gasket set. That comes with all the o-rings and valve guide seals, too. It's probably a good idea to replace the valve guide seals because of their age, cam chain too because of the work involved tearing one of these down. If you keep the bike for a while, you will end up needing and using most all those gaskets in the kit.
 
leave the pistons in the bore, just drop them out far enough to remove the gudgeons. see RG's post in above for how to tip the motor up to make it easy. cheers
 
Thanks for the tip on leaving the pistons in the bores. That would be a real time saver. In regards to replacing the circlips, I am not sure who the manufacturer of the pistons was. If I recall your never supposed to reuse them. I would imagine the circlips are specific to piston manufacturer. Is this correct? Where do you buy your Vesrah gaskets?
jefft
 
"not if your using the same rings"

I too am doing a top end rebuild. The bike has not been running for several years, and the engine had pretty bad leaks around the front of the head. Because of all the dirt and crud that had built up I thought to get the cylinders media blasted. Of course the cylinders will pick up some surface rust that will need to be honed off.

I don't need to replace pistons, but what about rings?
 
Measure your ring end gaps. If out of spec (which they usually are), replace them. Vesrah gaskets are available from 650Central.
 
5twins said:
sivarTi, get the complete engine gasket set. That comes with all the o-rings and valve guide seals, too. It's probably a good idea to replace the valve guide seals because of their age, cam chain too because of the work involved tearing one of these down. If you keep the bike for a while, you will end up needing and using most all those gaskets in the kit.
Click to expand...

I just went and added it up, makes sense to me. Looks like I'd end up with a ton of extra gaskets for about 2.00 more. The base gasket claims no 3bond needed but is it still needed for the head gasket? I'm hoping for one more ride today, maybe tomorrow then it's done for the year. Time to take it all back apart.
 
You don't absolutely have to apply sealer to the head gasket but, as outlined in the posts above, it's good insurance against future leaks. You don't use much, just thin beads in the areas indicated in the pic I posted. I apply it with a toothpick resulting in about 1/8" wide beads.
 
I have a few questions regarding gaskets. I am re-building my entire top end due to a head gasket blow out. I have the Athena gasket kit and I am just curious if these gaskets are directional? I see words on one side of the gaskets and nothing on the other sides. I thought there was some sort of adhesive released from the gaskets once the heated up but I am not sure. Lastly, I have a very slow leak at my clutch case cover, stator case cover, and starter motor gear cover. All were replaces with new gaskets and still a slow leak at all three. Should i apply a bonding agent from gasket to block side to cure this?
 
I'm pretty sure the head and base gaskets will only fit correctly one way because of the locating dowels. The only gasket treated with heat released sealer is the base gasket as far as I know. I don't use any sealer on the other gaskets, I just oil them with motor oil and let them sit 10 or 15 minutes before install. The oil soaks in and they puff up slightly. I've had good luck with them sealing this way. They also come off easily without the gasket sticking if you oil them. I use an in/lb torque wrench on all the multi-screw covers.
 
do any of you guys recommend using a scotch brite pad to clean off the gasket surface or a scouring pad or any sort?
 
I use paint stripper then gently scrape to remove all remnants of old gaskets. Final wipe down and cleaning is done with lacquer thinner. This dries quickly and leaves no residue behind. I don't use any scouring pad or scotchbrite pad.
 
I have found that a less than perfectly clean sealing surface will seep oil. Even a tiny spot of old gasket can keep it from sealing.
Scrubbing sealing surfaces with scotchbrite or other scouring pads might be ok, you ust have to be careful not to remove any metal from the surfaces. This will cause low spots.
Then it will leak even worse.
As 5twins said using paint stripper or a gasket stripper is very good.
Using a gasket scraper on aluminum can gouge the surfaces.
Leo
 
Yes, easy does it on the scraping. I have a couple old dull pocket knives that I use for the majority of my gasket scraping. Once the paint stripper does it's thing (let it soak on there for 10 or 15 minutes), that stuck gasket practically wipes off. If it didn't soften completely and soak all the way through, I re-apply. I now have and use this gasket scraper from Mike's (along with those old knives). It's a very nice high quality tool .....

http://www.mikesxs.net/product/35-8003.html
 
I have found that a platic putty knife that you use for sheetrock mud is fairly safe and works pretty well with a little softening through chemical means. That is what I used when I did my rebuild and there was no marring what-so-ever.
 

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