Epic fail. - Need to pull the head -

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Silent

Who said FJR's don't do dirt?
Joined
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Can you pull the head on the gen 2 without dropping the motor? I screwed up putting intake cam in, used the wrong alignment marks, and I'm prity sure I bent a valve doing it.

 
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I've had my motor out. NBD. Takes about an hour.

It WILL make servicing your motor boatloads easier.

 
It might be worth getting the timing right and do a quick comp. test. Maybe you will get lucky.

To answer your question the head will come off. there isn't much wiggle room but it will work. Make sure to get new head bolts along with the gasket.

 
I did the same thing on my Gen 1 a few years back. I simply retimed the cam and all was well. The timing marks on the cams allow Yamaha to use the same part for both intake and exhaust, so if you get one wrong then the two cams will work exactly at the same time and both intake and exhaust will open together. The engine won't run but the valves won't touch the pistons.

 
The bike ran "ok", just not "right" prior to starting this endeavor. I had the idle screw cranked to the hard stop and still only idling at 900. From my research, I went in to check the timing, and sure as snot, the exhaust cam was off by a tooth.

The cams are properly timed now, and the bike is knocking like theres a rod bearing out. so I"m 90% positive theres a bent valve. I only ran it for about 2 seconds before shutting it off, so I hope there's nothing too major to repair. I've already started tearing the motor out of the FJR. I know there's something wrong internally with the motor. The heavy knocking sound when I fired up the bike tells me that.

I'm getting flashbacks
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OK. I thought you meant that you had aligned the intake cam using the wrong marks on the camshaft itself, in which case it would have been timed exactly the same as the exhaust cam. That's what I had done.

Good luck, and I hope that all you find is a bent valve or two.

 
I ran a season with the INTAKE cam off by a tooth. No bent valves; but it ran a bit rough at higher RPMs and was down on power.

Did you turn the engine by hand after buttoning up / before starting? I'm curious if the valve interference would have been obvious at that point.

As for pulling the head .. I think it is possible. You'll need a pretty long and thin allen key to get the right side bolts off, and you may have to disconnect the left side wiring harness to get at the bolts there.

You'll have to remove the radiator, headers and throttle bodies to get the head off. Those are the biggest PITA's to get off; getting the out after that isn't too bad - you'll have to remove the rear wheel and shaft, engine mounts, support the engine then lift the frame enough to slide the engine out. The additional work to get it out where it's easy to work may well be worth it.

From my own experience: since the head gasket and bolts are not reuseable and will run you $80+s/h, after you have cleaned up / repaired the valves, put the head together using the OLD gasket and bolts (don't tighten them all the way) and do a leakdown test. If all is OK, then reassemble with the new gasket/bolts. It's a bunch of extra work, but at $80/pop it'll save you some $$.

Good luck ...

 
I thought the valves wouldn't hit if the cam is only one tooth off. I know two will grenade it, but thought one was the "grace period." This makes me want to pay for a valve check even more!!

 
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I thought the valves wouldn't hit if the can us only ibe tooth off. I know two will grenade it, but thought one was the "grace period." This makes me want to pay for a valve check even more!!
A.J. a valve check is no risk of changing the timing. This happened when taking the the cams off to do an actual shim adjustment, and even that can be mitigated by carefully marking and zip-tying the camchain to the sprokets. However, if you're nervous about it, that's good enough reason to pay for it if you have the cash. The odds are in your favor that a valve check will be okay and no need for shims. Silent was not living large and had to make adjustments.

 
Well, I got the engine out of the bike, took a LOT longer than an hour lol. Complete motorectomy

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Royal pain doing that solo I might add. I pulled the head, and after stripping 3 12mm sockets, 2 of which were 6 point, I wound up drilling one of the heads off of one of the bolts. Thing fought me to the end, but I won. Ok, now to the nitty gritty.

This is what happens if your timing is off by more than 1 tooth and you put the cam in. Tightening the cam caps put enough force on the valves to push them into the piston. No damage to the piston, just 2 bent valves on #1. Yes, I did try and turn the motor over by hand, and it was frozen. Pulled the cam but the damage was done.

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Lots of carbon build up on the pistons and head. And yes, those are brand new plugs.

 
I managed to do my ride around north America with the cam 2 teeth out of alignment. Idle sucked but it ran fine. 23000 km on that trip. when I got home I just realigned the cams Runs fine.

 
I thought the valves wouldn't hit if the can us only ibe tooth off. I know two will grenade it, but thought one was the "grace period." This makes me want to pay for a valve check even more!!
A.J. a valve check is no risk of changing the timing. This happened when taking the the cams off to do an actual shim adjustment, and even that can be mitigated by carefully marking and zip-tying the camchain to the sprokets. However, if you're nervous about it, that's good enough reason to pay for it if you have the cash. The odds are in your favor that a valve check will be okay and no need for shims. Silent was not living large and had to make adjustments.
Actually, for the record. I was fixing what the mechanic screwed up when he changed my timing chain. He missed by 1 tooth on the exhaust cam. From this point forward, monkeys can stay the hell away from my bike, I'll do it myself so I can screw things up proper!

 
Wow, you pulled the motor solo. I had 2 peeps helping me. Actually, I was helping them.

Aren't you glad you didn't run and run the engine hoping it would fix itself?

 
With knocking like that I'm sure it would have blown up long before I got out of the driveway Don. Bright side, only $210 in parts, not counting the head work. All the gaskets, and a lot of replacements for miss matched hardware that people have felt fit to hide all over my bike.

 
... carefully marking and zip-tying the camchain to the sprokets.
Now that's a GREAT idea!

Actually, for the record. I was fixing what the mechanic screwed up when he changed my timing chain. He missed by 1 tooth on the exhaust cam. From this point forward, monkeys can stay the hell away from my bike, I'll do it myself so I can screw things up proper!
Curious .. why change the chain?

 
After 50k miles, the bike was making a lot of internal racket from the timing chain. So I had both the chain and the tensioner replaced. The chain had stretched a bit, but I think most of the noise was a weak tensioner.

 
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