Should I tear down?
 

Okay so after seeing the Nikasil thread and TXCHOP's thread on his newest build and gathering more information in other places, I'm getting to be just a bit nervous about my 98" build. I've got roughly 5K miles on the build. If I hadn't seen these threads and other reports of the 98" problems, I would have no reason to think there was anything wrong with my motor. No noises, clunky behavior, excessive oil use (in fact I use very little) or any of the other indicators. But I'd rather not run around hoping that there's nothing wrong and later find out there was something that could have been done to prevent spending serious repair money.

So as of last night I had planned to do a leak down test and find someone here in Phx that had a bore scope that could peak inside. Finding a shop with a bore scope has proven to be quite difficult. From what I'm gathering the scopes are expensive, the recent MMI grads keep breaking them and results aren't perhaps as conclusive as you'd like and so those that had them don't anymore.

So then my plan changed to do a leak down test only and break into the motor if that showed a problem. But the engineer in me came out and I decided to take the top end off irregardless of what the leak down showed. The thought being that there may be some scratching of the cylinder that is not enough to cause excessive loss of compression yet. But if I'm going to do that, then why bother with spending the time and money on the leak down test?

Therefore I'm resolved to taking the top end apart. Here's how I see it:

Pros: I'll get definitive knowledge as to whether there's a problem or not. If not, it's worth the peace of mind knowing. If there is, I perhaps have caught it before the damage is so bad that I'm into excessive repair costs. If I do have the problem where the Nikasil shavings have caused problems in the lower end, it gives me an excuse to stroke the motor and get more power anyway! But perhaps there are still parts that can be saved. I've never torn the top end off myself and so this would be the next lesson to be learned by this neophyte motorcycle mechanic.

Cons: I've never torn the top end off myself and so the probability of screw up is elevated. It's prime riding season here in the valley of the sun and this will take away what little time I have to ride.

Am I overreacting?

Did you buy you 98" form GMR? If so call Steve before you do anything.

Piece of pie Moose. Can be messed up? Yes. Can it be done easily by the first timer? Oh yes. Buy the manual. More than enough folks in here to talk you thru it.

:pointnlaugh: :pointnlaugh: :pointnlaugh:

now thats some funny $hit right there thats how we got into this mess to begin with........:badmood:

One word...EMPATHY...the same road several of us traveled...

Well, Here's my take:

I opened up my top end because I bought a set of R&R stg 5 heads. They needed the pistons so they could fit the dome to the combustion chamber. So I tore it down after about 3500 miles.
When I pulled the jugs, I was disappointed to see some light scoring of the cylinder walls and the piston skirts. Nothing I could feel with my fingernail. But visible none the less. I had Reggie Sr take a look at them under his magnifier. He suggested I should send them back for RevPerf to evaluate.
I did.
I didn't get my original cylinders back. What does that tell you?
They put this permanent coating (teflon I assume) on the piston skirts.

They are going back in cuz' thats what I have.

We shall see.

That tells me all I need to know. The Fatboy is getting the tear down. Now finding the time to do this will be a challenge. I'll let you guys know what I find.

Thanks for the replies guys.

Got 20k on mine. Been to ES, Dragon, Montana, Sturgis. I am concenred about this, but I have trouble being to concerned. But I am watching my oil usage, it seems up. But know with 2 bikes, the 98" isn't getting as much attention.

Someone here bought some kinda fisheye from Sears, not sure how good it was, wasn't that expensive.

I am gonna do a leak down test. Thats where I would start. Theres alot of talk about bad cranks and excessive run out at VTF. That would cause alot of problems too.

Anyone notice Rev Perf is selling different coated "quiet" pistons with their kits now... We were just ginuea pigs.

Good luck with that Moose. You can do it!

I spent some time reading the service manual and it looks really straightforward. I'm going to have to get some gaskets and o-rings, but I was guessing that to begin with.

We'll see what tomorrow brings.

I'm guessing you're good if you've made it to 20K. If you were going to have a problem I thinking it would have shown by now.

I guess Axtell is making an iron version of the 98", so I may stick with that if there's a problem. Don't know really at this point what I'll do.

We're in the same boat Moose. I have the rev perf 98 with over 5K miles on it and was just about to post the same question. I'm glad you thought of boroscoping the cylinders. I didn't think of that and I have access to a boroscope. In your quest to scope your cylinders, take your bike to the general aviation area of Sky Harbor airport or go to a smaller county airport and find a hangar where some A&P's are working and ask them if they would hook you up. Take a spark plug socket with you and do it on the spot. It's an easy task.

I have not been reading all the dreaded posts regarding this subject because it pisses me off. I wonder how many of these set ups are running and what the failure rate is???????

cutting open the oil filter/getting an oil analysis might tell you something...?