hi all i need a bit of help, pulling my hair out here. get my bike started after a while, and when it starts it is only running on 2 cylinders, it is the two on passenger side that are running ok, but the other side will not run unless i squirt fuel in the head or put some down the bore, but will only run till that fuel has gone, i have put plugs in it, new ht leads coils, i am thinking now carbs or carb inlet rubbers, and how do i put these new inlet rubbers on as i got another set but they are really tight and just wont go on ,the number on the rubbers are mv9, but my old ones say something different than that, could they be wrong, as my old ones push on quite easy,any help with this i would be very gratefull, i dont know anyone near me with one of these bikes so can not iliminate any thing by plugging other parts to mine from another bike the same, any ideas what could be my problem anyone,

 

If the new Insulators as they're called are the right ones, then they should be snug. They are usually labeled as to which side faces the carburetor. Are these brand new ones that you're putting on, or used ? I will often use a little vasoline on the inside to help get them onto the carbs and intakes on the heads. The one I have here on a spare set of carbs has MALG on it.

 

hi thats what are on mine, but the mv9 ones just wont go on there, i was thinking of buying another set of carbs with the rubbers on so then it would be a bit easier and it might stop the missing problem on the two cylinders//

 

You did not mention if there was a problem with the rubbers in the first place or you are just trying to eliminate them from the possible cause of her not running on all four. I assume you have already checked you have a nice big blue spark on these cylinders. From what your post says, I would strip down all four carbs and give them a good clean. Jets out and an air line is best. Check your fuel filter and air filter whilst your at it aswell. Best of luck mate.

 

If you purchase old ones, then they're going to be in just as bad of shape as what you have now. They become hard and brittle. I'd suggest purchasing new ones, they're only about $11 US each, not a huge investment. You can re-use the clamps from the old ones.

Insulators Here (click)

 

going to take carbs back off in morning take them home and give them a good clean, how many jets in each one are there and do i check the diaphrams as well my reckoning its got to be carbs or fuel, i have new fuel filter to fit as well, the inlet rubbers i have are secondhand so will order set of them. i have a good spark any of you guys near my area or on a run out with any tips call in for a cuppa, really need this bike on the road, and its just beating me now every thing i try so far its a downer when you turn key on and still no fix,

 

Taking the carbs apart is an excellent idea. There are 3 jets in each carburetor. 2 are removable and one is not. It's the one that is not removable that you'll want to pay close attention to. Get a couple of cans of spray carburetor cleaner to help make sure you get those passageways clean. The idle air mixture screws should be removed before the cleaning process because the cleaning solvent will damage the O rings on it.

 

ok cheers will let you know the outcome

 

You can use the component identification post in the Sticky section to help you see what you'll be working on. The Idle Air mixture screw is also referred to as the Pilot screw. It needs a special D shaped driver to get it out. You should turn that screw all the way in just until it stops, while counting the number of turns. that way when you go to put it back, you can put it back in the same position. All of them should be roughly in the same position relative to each other.

Carburetor Components

Idle Mixture screw.




When I rebuild my carburetors, this is how they look when taken apart.


Good luck and let us know if you have any questions.

 

hi took carbs of cleaned them today, put them back on bike is running a bit better, but now i have to tip a bit of petrol in the carbs otherwise it wont start could all this problem have been the fuel pump,as once i get it started it keeps running it still misses and pops about , so its drawing fuel up once started but may be not enough, as i am thinking the fuel pump only pushes fuel in and pressurises, could this be so ,not that good at this part of mechanics, so what you reckon,,,