R6 First Start Fail - Help!

[CB ARGH]

Hey guys,

So we got the engine in today and got it running, however it is constantly running around 3krpm. The choke is off and the idle adjust screw is all the way out.

Any ideas guys?

[flashg]

Just a thought, the ECU might need adjusting to suit different engine, your Yamaha dealer should be able to do that easily.

[flashg]

Just checked, your bike 01 R6, its carb's of course . Sorry, was thinking injected.
Maybe carb balance could be out is all I can think.

[CB ARGH]

Just checked, your bike 01 R6, its carb's of course . Sorry, was thinking injected.
Maybe carb balance could be out is all I can think.

Thanks, I am using the carby off my old engine with the new engine and haven't touched anything.

[tigertim20]

vacuum lek would be my first guess.
what is the state of the rubbers between the intake and the carbs?

good way to check is to have the bike running, and spray something like wd40 around any areas (one at a time) that there are joins etc. if you hear an increase in rpm, youve found the source of the leak, and can sort it from there.

check any hoses or runners etc for splits or cracks etc.

Id also be double checking throttle cables arent routed wrong and pinched or jammed etc

[tigertim20]

Thanks, I am using the carby off my old engine with the new engine and haven't touched anything.

you still need to balance them.
the process starts with setting the valve clearances first, THEN doing the balance after that. be a good idea since its a new motor, to check that everything is in stock, and properly balanced and running nicely

[CB ARGH]

Thanks mate, the rubbers between carby and intake are in good nick. I'll have a good look at all the connections tomorrow to see if we've missed one and give that wd40 trick a go.

[YellowDog]

Have you tried physically forcing the throttle cable all the way back?

Sometimes they stick and it is easy to bend something, whilst you were changing the engine.

[CB ARGH]

Have you tried physically forcing the throttle cable all the way back?

Sometimes they stick and it is easy to bend something, whilst you were changing the engine.

Yeah it's definately all the way back. I've done a bit of hunting around the web and it does sound like a vacuum leak somewhere. I'll look into this tomorrow.

I have a feeling as to what it is - there was a tube connecting the airbox to the L/H side of the carby just above the throttle cable mount. I've got a feeling that wasn't put in correctly. I'll spray some CRC (is that safe) around the area and listen for a rise in engine idle speed.

[CB ARGH]

Have you tried physically forcing the throttle cable all the way back?

Sometimes they stick and it is easy to bend something, whilst you were changing the engine.

You were right. There is no vacuum leak. However the throttle isn't returning all the way. I've played around with the throttle cable adjusters both ends with no success. I believe it is the actual carby that is the problem, not the cables. I've run it for fifteen mins at idle with me holding the throttle back, I thought it may clear up since I'm sure the fuel has gone bad sitting in the carby for two months - that didn't work.

Help?

[awayatc]

Undo throttle cables....
Does the bike idle without cables ?
Either way you will then know wether it's carbs or cables causing it.....

[CB ARGH]

Undo throttle cables....
Does the bike idle without cables ?
Either way you will then know wether it's carbs or cables causing it.....

The bike does not idle properly with the cables removed. Cheers.

[Honest Andy]

Just wanted to say...
Keep going, you're almost there :niceone:

You'll be a KB guru by the time that bikes's on the road :cool:

[CB ARGH]

Just wanted to say...
Keep going, you're almost there :niceone:

You'll be a KB guru by the time that bikes's on the road :cool:

Shit I reckon!

Thanks for all your help so far guys!

Almost there...

[CB ARGH]

An update on the engine - I've dropped it off to my mechanic. It feels like I'm admitting defeat! The way I've got to see it is this bike will be taking me all round the country and it's got to be in the best nick possible.

Should be ready by Thursday.

[Honest Andy]

Fair enough! You've done all the time-consuming donkey work of finding a new engine and getting it installed. Hopefully now the mechanic will just have to give it a once-over, like getting a tune-up. And there's nothing quite as good as a professional tune :niceone:
You've done well, have a beer and start looking for your next project... a basket-case bobber perhaps...?

[tigertim20]

An update on the engine - I've dropped it off to my mechanic. It feels like I'm admitting defeat! The way I've got to see it is this bike will be taking me all round the country and it's got to be in the best nick possible.

Should be ready by Thursday.

nah mate, be smart enough to know when to call in the experts!
Obligatory wheelie vid when she's all running again!!

[Katman]

It's possible that the throttle mechanism is hitting one of the manifold clamps which is not allowing it to return all the way.

[CB ARGH]

It's possible that the throttle mechanism is hitting one of the manifold clamps which is not allowing it to return all the way.

After doing a bit more research I think it's the middle carby sync screw that needs to bring the butterflies back. Will find out for sure once the mechanic's had a look.

[neels]

The more you dig with half an idea of what could be wrong the more likely it is to fuck something up.

Someone who knows their way around will probably find some stupid little problem in 5 minutes and save you hours of swearing at the thing. Sometimes it gets to the point where taking it to an expert is money well spent.

Might as well get the thing properly tuned and good to go while it's there.....