Have you ever....

[loudbeard]

....seen a cam shaft jump timing under tension?

Here's the story:

Installed a set of cams in my S3R (with Degsy) and timed them according to the manufacturer's specification. Bike fired up and ran great, albeit lean. Verified the timing was correct after running the engine. There were reference marks placed on the cam sprockets, pretty simple process.

Bike goes off to Rob's Dyno for a tune. This entire process is a bit of a shit show. 6 weeks later it get my bike back with what seems like good results, bike runs good- for about a week. At this point it requires some throttle input to start and keep running. Won't idle, sounds like it's running on 2/3 cylinders. Since Rob- for whatever reason- decided to remove the O2 sensor I'm quite certain the problem is the tune not being able to adapt to different temp/pressure since the computer no longer knows if it's rich or lean. After talking to Rob about it he's basically not agreeable in troubleshooting the issue with me. "I can take a look but if it's not the tune I'll have to charge you for it."

Anyone who has dealt with Rob is probably familiar with his attitude. I decide to bring it to my dealer and have them reflash the ECU as the factory tune was the last time the bike was running properly. Dealer performs the reflash, nothing changes, the mechanic opens the valve cover and discovers the timing is off. The intake cam is off 3 teeth from correct position. So WTF? Has anyone ever seen this? Seems highly unlikely that a cam chain could go slack enough to allow the intake cam to jump teeth.

[Chippertheripper]

I'm assuming you know how lucky you are to not have smashed (some) valves to bits...
But no, I've never seen a ting chain jump.

[GixerJockey]

I'm a little curious about why it was away for 6 weeks getting a tune that should take two hours.

[Paul_E_D]

WOW, 3 teeth off and it's still running at all?!!

[GixerJockey]

WOW, 3 teeth off and it's still running at all?!!

Yea, I would have expected something to make motor-ending contact at that point.

[loudbeard]

The 1050 isn't an interference motor, basically the only reason I'm not replacing the head right now.

^ I am regurgitating this point...

Rob had numerous issues tuning the bike, I'd venture that all of them were self inflicted. Biggest problem was he had no clue on how to operate the TuneBoy software.

[Uncle Snake]

Cam chain tensioner?

[loudbeard]

The 1050 isn't an interference motor, basically the only reason I'm not replacing the head right now.

Ok this is flat out wrong. Margin for error is just a bit wider with a triple rather than an I4.

Seems like the only plausible solution is that someone (Rob) changed the timing on the bike.

Cam chain tensioner is fine.

[GixerJockey]

Seems like the only plausible solution is that someone (Rob) changed the timing on the bike.

.

This is the only explanation. If the chain jumped, then it wouldn't be just the intake cam that is off. And it wouldn't have just settled in, three teeth off, and continued to run. Everything would have smacked.

[Manny]

Did you ask him if he changed it?

[cdovego]

We can deduce that you won't be adding Rob's Dyno tuning to your sigline.

[SprintPoser]

Just glad it's not a trashed motor, and wondering why you & Degsy didn't work on the tune yourselves. He's pretty damned good with the Triumphs! (And just about all bikes for that matter.)

[loudbeard]

Did you ask him if he changed it?

Haven't made the call yet, just got the solution today. He'll be hearing from me soon.

We can deduce that you won't be adding Rob's Dyno tuning to your sigline.

No.

Just glad it's not a trashed motor, and wondering why you & Degsy didn't work on the tune yourselves. He's pretty damned good with the Triumphs! (And just about all bikes for that matter.)

Mainly because the tune is derived from a few very expensive bits of equipment which neither of us own. Tuning a modern fuel injected bike isn't real difficult but it does require having a dyno, wide band O2 sensor, and some expensive software. Agree though, Degsy knows his shit.