Finally got bike back but with problems

[tattootim1]

Hi all, Just looking for sugestions on where to go from here. Just got my bike back after an engine rebuild. Had Mike Rich pistons, 620 x 10 cam, heads done, etc you get the idea. The bike was running a Cliff Jefferies MyEcu and I could never get it to comunicate with my computer for what ever reason (probably me) and while away got a bluetooth unit to try when it came back. Anyway the bike shop that did the rebuild basicly didnt want anything to do with that as they didnt know how to use it. So the bike as it is seems to be running good, better than ever (no flat spot or miss anywhere in the rev range that ive gone to so far) but it is idling too high and the mechanic said he adjusted it as low as he could but its still 1500rpm when hot. Kinda makes it unrideable at the moment. I've put another Guzzi ECU off the race kits they bought out on it and no noticable difference in the workshop (didn't test ride as idle was still high). My question for anyone more knowledgabale than I is there a common cause to this symptom TPS or Throttle boddies, maybe somthing not dialed in right. If it was the ecu then I would have thought swapping it would have made a difference. Maybe its a symtom from the hight lift cam?.

The only other thing of note is that the bike is alot quieter. From the engine but also from the exhaust, it used to fairly bark when blipping the throttle but not any more. i cant understand that ???

 

Thanks for any sugestions on where to start.

Tim

[68C]

Is the cam timing correct?  if the exhaust valve opens later it can have the effect of slowing the outrush of gasses which you may perceive as a 'quiter' motor.  This could also have something to do with the fast idle although I can't think why.

 

Is it a case of being unable to get the motor to idle slower with both bi-pass screws fully closed - which may indicate air leaks between throttle body and cylinder head - or that the motor won't idle unless set to 1500rpm which may just be the nature of the hi-compression and hi-lift cam.  

 

It may just be that the motor has just been tuned to the point where the power band has moved higher and narrower, remember those old Brit 500's when highly tuned would not idle either and were useless on the road in town - a real hoot when wound up though.

 

Good luck checking it as of course the valve timing figures will probably be different from the standard V11.

[GuzziMoto]

Also, 1500 rpm is not really an overly high idle and should not make the bike unrideable unless there is something else wrong, like out of sync or binding throttle bodies.

And TPS needs to be set, or the bike can think the throttles are more open then they are (or more closed then they are).

[luhbo]

Do a complete basic tune-up. That means checking TPS when flaps are completely, totaly closed (that means without linkage, stop screws turned back, the flap laying directly at the intake wall), then go through the synchronisation procedure 1:1 exactly as it is described in the shop manual, then check how the bike's running now. Once you're used to this procedure and have understood what step stands for what you could try other methods. If you're a beginner you should stick to the manual.

 

Before you start push back the manifolds that come from the airbox so you can look at the flaps. In case they're open let's say 1,5 or 2mm you've found the reason for your problem. We had the same story over here some weeks ago. Bike came from the shop, did idle quite acceptable, but the owner said it was nearly unrideable. Flaps open, bypass closed, bike #@$&@#@ up, bill payed nonetheless :finger: The above described tune-up procedure helped him. 

 

A friend of mine owns nearly the same configuration. Pistons, cam, porting, twin plugs etc. The bike starts and idles absolutely flawless, maybe better than OEM even.

 

Hubert

[Kiwi_Roy]

I don't see how an ECU setting will make it idle fast, it could make it idle rich or lean but in my understanding the idle speed is determined by how much air it can suck in.

Throttle stops and bleed screws unless you have a leak in the intake rubbers

Do you have small rubber hoses attached between the two intakes, perhaps extra air is getting in there

 

I have a MyECU also

[mznyc]

Yup,I agree with those guys.Start with a base setting for TPS,bi-pass and balance,IF you can find no air leaks.The rubber boots are good at hiding small cracks.

[docc]

What Hubert said ^ (complete tune-up).

 

Re-check valve adjustment first (use at least "world spec" if not the looser "Raceco specs" for your edgier set-up).

[tattootim1]

Lets hope the cam timeing has been dialed in corectly! !. I have been reading a bit and come to the same conclusion, air leak and not tuned. He said that the idle screws were at their limit so to me that sounds like somthing amis. I will spend a few of days and go through everything. Maybe i can get the oxygen sensor working as well and the bike talking to the computer ala nirvana.

Thanks for your thoughts and i will let you know how i go

[fotoguzzi]

what Roy said, are the ports on the intake manifold either capped or tied to each other with a hose? if those nipples are open it will suck in too much air.

other wise it sounds like the TPS set to high, did the shop know how to set the TPS?

[tattootim1]

probably not, they mainly do harleys

[docc]

Not so much a surprise. My Guzzi dealer basically said if it starts, runs, and shuts off they weren't messing with it.

 

A patient owner with simple tools, a basic procedure, and a little time can work wonders with a V11.

[emry]

My Scura had a high idle when hot, although it was slightly intermittent. The bushings for the throttle shafts in the throttle bodies were oval. Sometimes the plates would closes all the way, sometimes not. I could move the throttle shaft (not rotating it) with the bike idling and get the idle to change. While I do have the bike apart currently, I have not yet tackled that issue.

 

Not to thread jack, but on another note my original aluminum flywheel is still crack free after 12k miles.     

[tattootim1]

What Hubert said ^ (complete tune-up).

 

Re-check valve adjustment first (use at least "world spec" if not the looser "Raceco specs" for your edgier set-up).

Thanks docc, its running new pushrods valves and springs so valve is diferent and they have just done them and checked after initial run

[tattootim1]

So it would appear that one of the rubber boots was leaking due to not been seated correctly (they look good but replaced them anyway). So now to check TPS and balance throttle bodies. On another note  I was having trouble with my MyEcu and I want to say Cliff Jefferies is one great guy. Just boxed everything up and sent it to him. Turns out my unit was very old and he upgraded it and sorted a bluetooth problem with with my Samsung tablet so we are now in business with Android optimiser

[mznyc]

Not to thread jack, but on another note my original aluminum flywheel is still crack free after 12k miles.     

How are you determining this emery?