Late Model CBR/GSXR Bike TB Question

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Steph
MegaSquirt Newbie
Posts: 8
Joined: Fri Jun 24, 2011 5:12 am

Late Model CBR/GSXR Bike TB Question

Post by Steph »

Hi, my name is Steph, and I'm new to the forum, and new to the field of electronic engine management. I have an early model Honda Civic with a SOHC 1200 engine that I'm building up, and a friend who races an injected 1200 is helping me to make the switch to injection. He has a big bucks conversion, with a lot of top shelf bits, whereas I'm working on a much smaller budget. Fortunately I have a background in electronics, so I'm not too worried about the DIY side of things, but naturally a little apprehensive, because there's always the chance you have problems to troubleshoot once it's all assembled. :?

Anyway, my query is related to what model of bike I can buy the throttle bodies/intake assembly from. I've already done the calculations and for what I have in mind, the 38mm throttle bodies are perfect, whereas my friend has larger TBs on his race engine. Initially I was intending to go with an earlier GSXR 600 intake with simple single injector throttle bodies (TBs), but as I looked for a set to buy, I saw the later ones had twin injectors and dual butterflies for better low-end response. The dual injectors are catered for with the MS-III (but not the MS-II?), it's the twin butterflies that worry me most, as I have no idea how difficult it would be to work with them. I was wondering if anybody had used any of these later TBs and whether the second set of butterflies can just be left in the open position (hopefully their default), so my only issue to deal with will be the twin injectors, which is a feature I'd really like to have? Perhaps the secondary butterflies can just have the 2 screws removed and take the 'butterfly' out altogether, just leaving the shaft behind?

The engine I'm building is for the street, and as such I am also hoping to buy an intake that doesn't look too utilitarian, which is why I like the earlier TB assemblies, as they're simple and easy to dress up, whereas the later ones are really quite busy, but that's likely pollution gear that I could remove.

Thanks in advance for any input you might have,

Steph
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Steph
MegaSquirt Newbie
Posts: 8
Joined: Fri Jun 24, 2011 5:12 am

Re: Honda Bike TB Question

Post by Steph »

OK, I ended up going with a CBR600F4i intake as it's got 4 nozzle injectors, and it's off a Honda, which is great because I think it's better to keep it all in the family, rather than putting Suzuki parts on a Honda. The beauty of these TBs is that they were the first generation of TBs to reach the inline-4 market, and as such they are still reasonably simple without the twin butterflies of the later models, and other complexities as well.

OK, back to reading the MS-2 manual :RTFM:

Steph
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