Revving to 7k then flat

[Xenocide]

Just thought i'd post up about this.

Recently I changed my CCT's to manuals and when removing the one on the rear cylinder it slipped meaning i had to reset the cams. Well I managed to rock up basically and set the 180o out. Meaning when it was ridden:

• It sounded boomy/hollow
  Revved / revs to 7k then stops like it's hit a limiter (about 100mph)
  Keeps stopping/almost stalling then carrying on at idle / low RPM. Disconcerting noise.

Whip the cams out and reset properly, and it's fine. To do this find TDC on the front cylinder (compression ( whip off the cam cover, it's not as hard as everyone makes out. 15 mins and you know it's done properly) ) then rotate 1 1/4 turns (of the crank) to find rear tdc, and set cams so the RE/RI marks are level with the head on the outside.

Runs much better now but still makes the weird stopping thing when idleing. It's been dynojetted so i'll put it down to that. Also while you're there, take the covers off the cam chain and set the tension on properly (if you have manual CCTs). There's some confusion about this due to a misprint on the APE CCT instructions. Basically you should have 6mm TOTAL SLACK (NOT DEFLECTION!!) between the cams. This means 3mm each way from it's resting position. That's 3mm deflection, 6mm slack, not 6mm deflection as originally stated.



Hopefully that might help someone who's had some problems.

(P.S I think that's the right procedure (was a while ago now), worked for me anyway. If you would like to make any amendments, let me know).

[VTRDark]

Nice write up and nice diagram. Your not wrong about removing the front cam cover, it's not that hard and gives one peace of mind. I messed up the tension doing mine by feel so removed it and got spot on accuracy.

(:-})

[tony.mon]

Good clarification.

Re idling stalls, it's caused by two factors, the carbs being out of balance doesn't help, but if you turn tickover up to 1400 it helps.

It is worse if you fit a lightened flywheel, by the way.

[Xenocide]

Lovely thank you.

Just to clarify, it does (something) like this. But mine's a bit more violent (I assume because it's idleing lower)

[tony.mon]

Yep, it's a standard Storm airbox cough- they all do it to a greater or lesser extent. It's the inlet gases igniting in the carb throat and airbox.

Doesn't cause any damage, and balance the carbs/turn up the tickover and it pretty much disappears.

[Xenocide]

Thanks again tony, that's put my mind at rest!

Well i'm off around europe on it on Friday so let's bloody well hope it's ok . 4k+ miles. w00t.