1986 VFR 750F Carbs

Hey,

Ive got an '86 750f and recently found that my throttle bodies are worn and wont seal around the shutter. My question is does anyone know where I can come up with a carb assembly to replace these? If not, can I take them to a machine shop and get them bored or polished? Please let me know if you have any ideas.

Thanks,
Nick

 

I sent you an email...

I've got a project bike that we took the engine out of... my friend took the carbs, and is going to swap his out. Let me ask... I just don't know if he's got time to take them out... but we DO have another set.

 

If I'm interpreting your statement correctly, the throttle shaft plates (think you call them 'shutters') are not sealing in the carb bore.

Typically, the plates are fastened with staked screws so the screws will not come out. If the plates have been removed, the person may not have installed the plates correctly - leaving a gap between the plate and the bore.

Loosen the screws and allow the throttle to snap shut several times. This should center the plates in the bore for you. Then tighen up the screws and re-stake them.
(Tip: some computer screws will fit if you have to remove the staked screws - just be sure to loctite them in)

The plates have a chamfered edge to them so they will seal to the bore when the plate is at a slight angle. Twist the throttle shaft so you can see the edge of the plate. Verify the chamfer is on the correct side of the plate.

Someone may have put different plates on the carb. If they did that, no telling what else they did to the carbs. Thoroughly inspect the carbs to ensure everything is in it's proper place, works correctly, and is the proper part.

P.S. Never heard of throttle bodies being too worn to be used. History of the carbs or bike?

 

This was a common problem with old English sports cars that had SU carburetors. Way back in time, there were places that specialized in reaming out the carb bodies and adding bushings to tighten them up. The link below is for a shop in CA, but might not be a bad place to start for some info;

http://www.recarbco.com/

In the past, they have resurrected some marine carbs for me that I figured were beyond salvage. They used to do excellent work.

 

SU carbs!! What as blast from the past!

Don't forget to fill your dashpots!!!!!

 

That's right! And if you want that extra bit of performance, use WD-40 instead of... uuh, I don't remember!

 

I'd like to see that. I've not heard of carbs "wearing out" like that before.

It sounds like you are talking about the slides, maybe? If so, those are not supposed to seal. I'd double check, the carbs that you have might be A-OK.