Throttle Body problems .

Tim Clancy

i recently had my 04 busa in for full topend clean up and rebuild. now they are saying my throttle body is stuffed after being soaked and cleaned to reveal wear around the butterflies.. i belive the sensors are ok... the shop is telling me that this is a first and never heard of before.. any ideas ?
Re: Trottle Body problems .

Anything with moving parts is subject to wear. What the shop is most likely talking about is wear to the pins that support the butterfly valves. Rarely does any significant wear take place between the round plate and the bore of the throttle body. Yer bike is almost 10 years old,but is it a high mile'r?

The reason they have said they have never seen it before,is due to the fact that they haven't worked on many bikes or very many Busa's. Its not a common thing to see,but you will run across it working on anything with carbs or TB's from time to time.

The condition makes it hard to tune a motor because the worn part now allows air to enter where none exsisted before.

Hope that makes sense.

The red arrows I have drawn show where the TB's usually wear out and allow air past...the green arrows point to the secondary wear point where a plate has come loose,is slighty bent,etc (highly unlikely).

It is rare to see on something machined as well as a Busa...but it could happen. That or the shop could be taking "you for a ride."

Thats why I asked if you are sitting on a high miler. If you are skepital,ask them to show you the wear,there will be play between the rod that holds the four butterflys (yellow arrows) and the 4 bodies.

Hope that helps.


tb d.jpg
Re: Trottle Body problems .

I have NEVER heard of a set of Busa throttle bodies going bad. A bent blade from a nitrous pop or turbo backfire? Absolutely! But never just wear out.
Re: Trottle Body problems .

Dayum Race Filters :whistle:


Best of luck brother, a first indeed and we have several +100K mile bikes running like scalded dogs around here. And nobody babies these bikes.
Re: Trottle Body problems .

Even with wear they should be able to do a fairly close balance of the bodies then adjust the fuelling to match if needed.
Sometimes the plates get bent by mr clumsy and yes as the air and any unfiltered dust etc passes through the gap between the plates and the body bore it will cause wear but given that gen1 busa's can do 100k miles without needing new bodies I find it hard to believe yours are so badly worn that they would need repaired/replaced.
I just wonder did they take them apart and damage/scratch something whilst cleaning.
If your bike has a PC3 or they have a Yoshi box etc they should be able to build the bike back up with ease.

I'd get them to prove its worn rather than take their word for it.
Re: Trottle Body problems .

50,000 kilometers.. i have seen the TBs and yes there is a bit of wear around the butterfly areas and more light gets through.. they tried a set from another guys busa and that worked, then they tried another set with 12000 on them and that didnt work.. all electrics and sensors have been checked and ok.. it just runs too rich, to much fuel going in.. so now the shop mech is scratching his head and into week 8 i have no bike still..
Re: Trottle Body problems .

by the way thanks for your thoughts guys... maybe its time to look at a new 2013 busa with the brembos and ABS, no braided lines tho, hehe
Re: Trottle Body problems .

fourth set of throttle boddies worked so im back riding.. suzuki still cant quite work out the problem..
Re: Trottle Body problems .

yes they were synked twice before the head gasket went, kind of funny.. a 700dollar service,valve adjust throttle synl etc and on the way home the head gasket blew.. howz that , lol