High revs sticking throttle.

Hi lads having bother with high revs when engine warms up and I blip the throttle, after doing a spray test with wd40 I think I have sussed out it is an air leak at the boots from the carbs to the engine or the throttle seal on the right hand side.
I have a spare engine with boots on when I took them off there is a gasket there which is in bits does anyone know where I can buy these in the UK?

 

Idk about buying parts in the UK but member Chacal (also Len) is our resident parts guy. Click the icon in the upper right corner or start a conversation with him.

Gary H.

 

Yambits should have the gaskets in stock. If not then you could order through your Yamaha dealer, as they are still a current part.
If neither of those options work out then Chacal does have them, and does ship internationally.

 

Hi bud tried yambits with no joy i will try and find a local yamaha dealer.
Can the instant gasket in a tube be used with rubber?

 

You can use RTV, but it's really better to have the gaskets so the boots are at the correct distance to the airbox (the airbox boots might not quite sit in place correctly otherwise). Many of us have used it as an adjunct to the gaskets. I personally like the Permatex copper gasket dressing.

 

Do any other models gaskets fit the 750 boots?

 

Yes. http://www.yamahapartsnation.com/oemparts/p/yamaha/4h7-13556-11-00/gasket-manifold

 

I make my own intake gaskets. I'm sure there must be an auto parts store on your side of the pond that sells rolls of gasket material. If so lay it flat on a surface like a piece of plate glass , using a sharp exacto knife push manifold down on material cut around it use it as a pattern. I use a sharp drill bit to cut the holes for the allen bolts. Put a light smear of grease on both sides of gasket and should be good to go. I have used this same roll for years on my other bikes and my beloved air cooled Beetle. Before anyone asks yes just did my 82 750 Seca this way used propane and carb cleaner no leaks ! But you should consider ordering from Chacal at XJ Forever if you feel this is beyond your ability .

 

if you ink the boot it will leave a print on the gasket paper to cut to

 

try "wemoto" they do the gaskets for my xj600 , you can check their website to see if they do the 750 ones,
http://www.wemoto.com/bikes/yamaha/xj_600/84-90/picture/carburettor_to_engine_inlet_rubber_-_gasket/
but as stated earlier its easy to make your own, I did for my 600, by drawing round the boot
stu

 

Thanks to everyone for the input I have ordered some from we moto they arrive tomorrow with some more bits n pieces that I needed (well more wanted than needed but I told the wife I NEEDED them, haha) will i need any kind of adhesive or do they go on dry?

 

Use a light smear of grease on both sides help to seal ,and if you ever have to pull boots might save gasket.

 

Cheers bud : )

 

Sometimes the gasket alone won't seal the joint even with grease on them. If you still have a vacuum leak after installing with new gaskets, pop them back off and coat them with a gasket dressing or a thin smear of RTV.

 

When I fit the carbs back into the boots should I apply anything to help stop air leaks between carbs and inlet boots?

 

Some members might apply a dab of silicone grease to make them slide in a little easier but I don't use anything. The snug fit and clamp should seal the boots to the carbs.

Gary H.

 

a little assembly grease on the carbs.

 

I just use swear words. Seems to work.

 

Lol. Best tools in the toolbox.

Gary H.

 

Haha I've learnt a lot of new swear words and made up a few of my own since starting this build.
It normally comes out when a spanner slips and I take a chunk out of my knuckles! : )