Hey all! I've recently been chasing an oil leak, and I was wondering if anyone else has experienced similar issues. I replaced all of the grommets for the top of the valve cover but I'm still leaking oil on the right side of the bike.
I believe its the capped nuts and washers that are in the valley with the spark plugs. I was also looking on Partzilla and seen that they have two different washers listed. Is this correct? Lastly is there anywhere else that I could source these parts, i.e locally or through rpm?
Thank you all and hope everyone has been well.
Here's some pics I forgot to add
The right two studs are oil galleys they are sealed at the nut with copper washers found here https://www.rpmracingca.com/proddetail.asp?prod=90201-10128
If is leaking between the head and the barrels then it is the dowels seals and the head will have to be removed to replace. We have those in stock as well.
Right on Robert thank you sir!
Johnny,
Clean off all the oil, and spray the area with aerosol body powder. When you start the engine, the dry powder will get dark first where the oil comes from. Shut down the engine, before the oil goes everywhere. Then you will know exactly what needs fixin'. :yes:
Will definitely try this Red, you're the man!
What weight oil are you running and is it conventional or synthetic? Just curious because if you are running 10-40 synthetic I wonder if 20-50 conventional would reduce the leak
Quote from: 86FJNJ on October 17, 2025, 07:38:12 AMWhat weight oil are you running and is it conventional or synthetic? Just curious because if you are running 10-40 synthetic I wonder if 20-50 conventional would reduce the leak
86FJN,
Maybe so; synthetic oil is a smaller molecule than dino oil. People who switch to synthetic oil often have a few leaks they never had before. Once you seal up these new leaks, though, the machinery will last much longer than it would on new dino oil every few months. Those l-o-n-g powertrain warrantees on new vehicles come from using synthetic lubes, not from better designs of the machinery. Usually you will get better gas mileage with synthetic oil, too.
I haven't changed the oil on this bike yet, but I want to say that PO was using 10w40. I'm going to move forward with swapping the copper washers first.
Oooooh, oooooh, oooooh...this is turning into an oil thread!
Mr. Kotter, Mr Kotter, Mr. Kotter....
(popcorn)
Quote from: JohnnyTheCraneGuy on October 17, 2025, 11:27:21 AMI haven't changed the oil on this bike yet, but I want to say that PO was using 10w40. I'm going to move forward with swapping the copper washers first.
Do one head stud at a time. Do not loosen both at once.
Quote from: red on October 17, 2025, 09:14:14 AMQuote from: 86FJNJ on October 17, 2025, 07:38:12 AMWhat weight oil are you running and is it conventional or synthetic? Just curious because if you are running 10-40 synthetic I wonder if 20-50 conventional would reduce the leak
86FJN,
Maybe so; synthetic oil is a smaller molecule than dino oil. People who switch to synthetic oil often have a few leaks they never had before. Once you seal up these new leaks, though, the machinery will last much longer than it would on new dino oil every few months. Those l-o-n-g powertrain warrantees on new vehicles come from using synthetic lubes, not from better designs of the machinery. Usually you will get better gas mileage with synthetic oil, too.
What do you mean by long powertrain warranties? I'm not aware of any on bikes. On cars they are usually 5yr/60k which is really not that long when you think of the price for a new vehicle and the actual potential life of the vehicle, the manufacturers liability is very low in that window. If you purchased a new car and the engine or trans died after 5years and 1 day or 60,001 miles you would be really mad, because you know it should last 2-3 times that. Yes synthetic oil is better in those aspects you mention but the long service intervals are really to get the cost of ownership number down but I would not suggest anyone follow their mfg's 10k mile oil change intervals if you want your vehicle to last longer, while synthetic is better it still gets dirty and diluted at the same speed as conventional oil and should be changed.
86FJN,
"Power train" is everything from the fan to the rear wheels. Some new "vehicles" (not bikes) have 100,000+ mile power train warrantees. As for the rest, I never said otherwise.
We now return you to our regularly scheduled mayhem. :biggrin:
Well guys, I got the washers swapped out and she is still leaking. I didn't have the chance to grab that body powder but I'm ordering that shit right now. :dash2:
I've confirmed that it's still coming from the right side rear head nut. The front one is fine now, no signs of oil around it, but the one towards the rear is still leaking like crazy once the bike starts warming up. Torqued the head nuts to 26 ft lbs and still did one at a time.
Was I supposed to heat the washer first before installing? I didn't see any mention of this in the Haynes manual but I have seen somewhere that heating the washer and making it softer will help with sealing. Could I also use Red RTV Silicone on the washer?
Quote from: JohnnyTheCraneGuy on November 04, 2025, 02:44:55 PMWas I supposed to heat the washer first before installing? I didn't see any mention of this in the Haynes manual but I have seen somewhere that heating the washer and making it softer will help with sealing. Could I also use Red RTV Silicone on the washer?
Pass on the RTV
Take the copper washer out, heat it up to soften it and try reinstalling.
I've done that trick on re using copper crush washers on brake line steel banjo fittings
LA Mike told me about that trick years ago...I think he called it re-anealing.
Now I always use fresh aluminum crush washers with my Spiegler aluminum banjos.
Let us know how it works.
will definitely report back :hi:
Well I finally traced down the culprit of the leak! It's coming from the damn intake side of the valve cover gasket where the semi circle is :dash2:
Its sucks because the PO had just finished doing the valve adjustments this summer so its still fairly new, oh well! :hi:
If it was a new gasket, you should be able to reuse it.
Some RTV on those half moons should do the trick.
Don't use RTV on the entire gasket, Randy yelled at me for doing just that....but I will say, that fucker didn't leak.
Alas, poor Randy had to use a crowbar to get the valve cover off.
Good for you in tracking down the leak. Kudos.
Gotcha, Pat!
Will definitely try not give in to the temptation of that although it is strong :rofl2:
Totally forgot to post an update here.
I was able to pull the cover, apply RTV to those half moons, and rerun the gasket.
It's been about 130 miles and she's happy again!
Still gravity fed for now but still happy :rofl:
Good on ya...