Airhead

Me too, its boggling, I know its a daft question and that you will have done this already, but im gonna ask anyway Can you see unobstructed passage from all the carb manifold connections to the air box and unobstructed passage from air inlet to air box??

Yep...Its suits you!

I expect so yes, I will try to find out more.

Ok if its not the carbs, did you check the fuel delivery to them?

Hi Rasmus, I can suggest five things 1: Check the carb floats are not leaking, Hold them with pliers in a container of hot water, watch out for bubbles (be careful not to bend the tang that operates on the float needle valve) 2: Check the float height is correctly set to 23mm 3: Using a good magnifying glass and a small light source (such as on a mobile phone) have a look down the pilot air passage and verify that the air jet is clean, this is often overlooked, if you use a compressed air line you should be able to blow through this to find air comes out where the emulsion tube (needle jet) screws in to the carb body, also check the very small holes in the side of the emulsion tube are clear. 4: Try again with the air filter removed, if it improves clean the filter 5: Carbon build up around the exhaust port, scrape clean if necessary, Best done with the head off and a rag covering the piston crown.

Pretty much the same but there will be the obvious differences, Barrel, Head, piston, carb. As for the ignition sys if you compare part numbers between 125 and 175, that would be the best indication.

You should strip the carb down again, sounds like two problems to me 1: Blocked pilot jet, hence the need to bump start it. 2: Fuel level too high in carb, (Runs like it is choked) Check the float height is set to the correct specification. 21mm

have you done the 'suck' test on you vacuum fuel tap and got a good flow of fuel?

Give be a barrel any day Jim

Hi, can you explain this in more detail?

Engines dying when hot can be pickup coils for electrnic ignition going open circuit or even the ignition coils themselves Cant explain the airbox phenomenon though, thats got me scratching my head, next time it dies can you check for sparks on pots 1&2 . Fuel starvation can also be a problem, if the fuel filter (wherever it is) is getting blocked. but i would only expect this symptom if you were running in 'Prime' position on your fuel tap! Im interested to know if youre running in prime position though (assuming there is one on your bike)

This is a new one on me, that is some fuel burns and some does'nt, Never had a power valve bike myself but i'm wondering if this could be the culprit, ive heard they can stick, somehow they rotate in the exhaust port i think, can you check its workink correctly, have you got a manual etc etc, try you tube too, sometimes people put useful stuff on there!

Both exhausts or just one, do both exhausts get hot at the header pipe?

As above have said, special attention to speed though, 30 for me is an absolute maximum because some car / van drivers will try queue jumping by driving up the ouside lane and will jump sometimes quite recklessly back into the inside lane further up the road, this is usually when the outside lane moves quickest but ends up in a right turn when these drivers really want to go straight on, you do need to be going slow enough to stop if they do this in your path!! Wing mirrors...Dont try squeezing through too small a gap that youre colliding with vehicle mirrors, you wouldnt like it and neither do they. If you see someone deliberately move to let you through, try to acknowlege it if you can do (a little wave, thumb up) Safe riding

Don't worry about it, I got it: Another dangerous statement, meaning this is something that a woman has told a man to do several times, but is now doing it herself. This will later result in a man asking 'What's wrong?' For the woman's response refer to "NOTHING"

It may feel ok, Theres no different "Feel" even when its toast!! But the symptoms suggest fooked, or at least that an adjustment is needed either at the lever or if thats still got free play, then at the pushrod adjuster (If its got one) Double post not intended...sorry, damned pc

It may feel ok, Theres no different "Feel" even when its toast!! But the symptoms suggest fooked, or at least that an adjustment is needed either at the lever or if thats still got free play, then at the pushrod adjuster (If its got one)

If you once got 73mph @8000rpn and now you get 63mph @ 8000rpm Then it is clutch slip!! Have you changed oil recently, full synthetic oil can cause this, or did you thrash it to death during its short life and wear it out? Make sure you have a few millimeters free play at the lever before it starts to pull on the cable, adjust as necessary!

Tiger Woods drives his BMW into a petrol station in a remote part of Ireland. The attendant, who knows nothing about golf says “top o the morning to yer sir” Tiger nods and bends to pick up the nozzle. As he does so, 2 tees fall out of his shirt pocket “What are those?” asks the attendant. “They’re called tees, they’re for resting my balls on when I’m driving”…”Feck me” says the Irishman “BMW think of everything”!!

No all it is Gene is a vacuum operated fuel tap (Petcock), when the engine is running a vacuum is developed in the manifold, this vacuum pulls the diapragm over in the fuel tap, thus allowing fuel to the carbs. So its not any benefit to split the line to all manifolds because a vacuum is a vacuum is a vacuum and a vacuum is all it needs Heres some info, dont know if its readable, maybe if you print it, plz let me know.

Hi and welcome, Its been asked before about manuals Here not sure what the answers are, suggest you ask Markyboy27

Yes could be the coils breaking down, could also be the pickup coils breaking down for the electronic ignition, But as i say make sure you have a good unrestricted fuel supply

Not sure about that Mikey mine was made with it already on, just another reason why its the best bike Yamaha ever made When you change your back sprocket and fit the wheel, shove the wheel forward in its slots to give more free play in the chain while you fit the link.

Good to see you again Mikey I use pliers myself, does your bike have a spring loaded chain tensioner, If so pull it away from the chain while you get the link in, When it comes to the pliers and spring link its wise to wrap a bit of tape round it to keep it from flying away if the pliers slip !

Only joking, but honestly i cant remember, Have a look under the seat or under the tank, Yes look under the tank