FJRiders.com

On Sunday with the help of another FJR owner we did a valve check/adjustment on my Gen II. We found 2 intake valves at the very minimum clearance and 1 below minimum. We changed the shims on the 3 valves and buttoned it back up. Bike starts and seems to run okay but this morning on my way to work it did something it had never done before. At steady throttle, around 70 mph in 5th gear on the highway it surged and felt like it was going to shut off. I downshifted to 4th and was able to accelerate through the "flat spot"? I came home today and replaced all 4 of the caps for TBS as we'd noted they had some cracks in them. My fuel tank was low so I just went and filled up and took off for another test ride. Regardless of gear position if riding at a steady engine speed of around 3k if I give the bike throttle it kind of surges but doesn't really want to accelerate or take fuel. Downshift and get the revs up and it accelerates but just seems like it's not as peppy as it was before the valve adjustment. We zip tied the cam chain at the crank, zip tied the exhaust cam to the cam chain and marked the intake cam and cam chain with a paint marker and it looked like all of the marks were lined back up when we buttoned it up.

Thoughts?

BkerChuck wrote: ↑Mon Apr 08, 2019 6:41 pm ...At steady throttle, around 70 mph in 5th gear on the highway it surged and felt like it was going to shut off. I downshifted to 4th and was able to accelerate through the "flat spot"?...We zip tied the cam chain at the crank, zip tied the exhaust cam to the cam chain and marked the intake cam and cam chain with a paint marker and it looked like all of the marks were lined back up when we buttoned it up.

Thoughts?

You did remember to release the screw on the back of CCT?

If it's not developing horsepower at 5000 rpm plus or does so slowly, good chance the cam timing is off a tooth. Hate to tell you but the only way to know is to take the valve cover off. Ensure CCT is extended as Alan says, rotate crank until #1 TDC and crank timing mark aligned to the split in the engine cases. If you can't gunsight the timing marks on the cam sprockets, verify the "dot" on the top of #4 cam lobe is aligned with the vertical rib on the outboard end of #3 cam bearing cap.
You've done no damage, and it's easy to get a tooth off. What I do is double check by rotating the engine 360 to ensure all chain slack is taken up, get it to #1 TDC again to verify timing is OK.
Pic of project bike cams, no chain, not bolted down but you'll get the idea. The vertical ribs have some faded white paint on them.



Edit, added pic of cam sprockets for reference

It's that surging that gets my attention. Like there is some slack in the cam chain allowing the cams to vary in timing.

CCT definitely released fully and chain is tight. Rotated engine more that 2 full revolutions. I was wondering if it might be off 1 tooth. Just refilled the damned fuel tank too! Won't hurt to ride to work until the weekend and use up some fuel?

One more thing, check the right timing cover and that the ignition pickup wire is not pinched between the cover and the engine case..... likely near the top. Can cause a performance issue. Sure, ride it. I had a buddy with the problem for quite a while, had it to a couple of shops, even changed his ECU. Then I got to ride it and kinda knew right away it was cam timing. I have fixed two FJR's with the pinched wire syndrome.

I saw some reports about the pinched wire issue in the other sandbox and checked that last evening. Didn't fully remove the right side fairing panels but loosened them enough to get at the timing cover. They do not appear to be pinched in any way and I can wiggle them freely enough leading me to believe that is not the issue. Will pull the cam cover back off and check the timing marks Saturday afternoon. No chance to get to it before then most likely.

When I did my valve check, I put the ty rap on the lower chain, but I did not put it close enough to the lower sprocket. When I took out the CCT {I changed that also at the same time} I looked down and saw that the lower chain was hanging just BELOW the sprocket. DANG. I immediately pulled it back up and retied the ty rap closer to the sprocket and continued to replace the out of spec shims. After everything was done, I tried to make SURE that it was in time, but I did NOT know about the method Rayzerman mentions above and with the engine in the bike the other way makes it very difficult to make sure. So I buttoned it up and hoped for the best. STILL, every time my bike so much as stalls, or gets lower than average gas mileage, I wonder. LOL

I learned the hard way while working on LCB's bike to check ALL the timing marks after releasing the tensioner and at least one full rotation before putting any covers back on. Just glad I didn't do any damage.

While each camshaft is loosened, I used some liquid paper on the cam gear timing mark, wiping off the excess. This makes it much easier to see the timing mark when the motor is back together. That liquid paper reflects beautifully on the flashlight.

I guess I know what I'll be doing this weekend.....

Thanks to all for the help and advice.

BkerChuck wrote: ↑Mon Apr 08, 2019 8:24 pm Just refilled the damned fuel tank too!

Meh, that just makes the tank a little heavier. The thing to bitch about is that damn coolant pipe.

raYzerman wrote: ↑Mon Apr 08, 2019 8:05 pm If it's not developing horsepower at 5000 rpm plus or does so slowly, good chance the cam timing is off a tooth. Hate to tell you but the only way to know is to take the valve cover off. Ensure CCT is extended as Alan says, rotate crank until #1 TDC and crank timing mark aligned to the split in the engine cases. If you can't gunsight the timing marks on the cam sprockets, verify the "dot" on the top of #4 cam lobe is aligned with the vertical rib on the outboard end of #3 cam bearing cap.
You've done no damage, and it's easy to get a tooth off. What I do is double check by rotating the engine 360 to ensure all chain slack is taken up, get it to #1 TDC again to verify timing is OK.
Pic of project bike cams, no chain, not bolted down but you'll get the idea. The vertical ribs have some faded white paint on them.



Edit, added pic of cam sprockets for reference

Great pictures. I have this exact same thing going on. I did rotate the engine over through several cycles to make sure I didn't have and valve to piston contact. Bike starts and idles, when you open the throttle it stumbles badly. Fortunately, I have not buttoned everything up yet, so Back in I go. I did the zip tie method too.

Reading the tech manual to verify the timing, it says after you set the exhaust cam, to make sure the timing chain is tight (no slack) back down to the crankshaft gear. After that to set the intake cam with no slack to the exhaust cam. I think my problem occurred when I didn't verify their was no slack from the exhaust cam to the crank gear.

As a side note, I had to adjust almost every valve. My bike does get a pretty good workout as I ride two up and tow a trailer 95% of the time. I do run ring-free with every tank. I also have a PC5 with autotune module. Hopefully tonight I can get this sorted out.

I confirmed that mine did slip a tooth. I tired to simply move the chain one tooth on the intake cam, but it still is not lining up correctly. I'll have to loosen both cams, set them and the crank properly with #1 at TDC, then put the chain back on and the tensioner. Is a PIA to see the marks with the engine in the bike, but doable.

Glad you got that sorted...

Mine was indeed off one tooth. Fixed it this morning and test ride revealed we indeed found the missing power and throttle response. Thanks to everyone for their help and advice.

There ya go, cool!