Author Topic: BMW bike throttle bodies K1200 etc. (Read 5990 times)

Mr Doricar · « **on:** November 21, 2010, 09:18:14 AM »

Theres a guy local to me who specialises in TiG welding and making up manifolds for carbs/throttle bodies for local rally drivers. You give him a spare manifold and the throttle bodies/carbs you intend to fit and he will make an appropriate manifold or adapter for you.

Give him a spare manifold and he'll cut it down to just a flange and fabricate the rest.
Or
Give him a gasket and he will CNC cut a flange to the correct shape

I'm being a bit ANAL here, but i'd like to stick to BMW products for my M42 so I'm thinking about asking the guy to make some K1200 or similar throttle bodies fit a spare M42 inlet manifold I have.

What do you guys think to this? Do you happen to know how much power K1200 could flow? Or are there similar 4 cyl. BMW bikes that would have a better system?
Any advice would be appreciated.

Don't worry about telling me about throttle pos sensor / MAF etc. I can sort that out myself.

Thanks

James-

DesktopDave · « **Reply #1 on:** November 21, 2010, 10:48:41 AM »

It's a great idea to use those TBs. I have a set of Keihin 38mm bodies (from a 2006 R6) that made me think along the same lines. It's too much work for me though. They'll flow just fine and even use a very compatible Bosch system. Bore spacing and linkage modifications will be your big problem. I'd get the M42 manifold machined to accept the TB boots that many motorcycles use. You'll need an aftermarket ECU as well, like MegaSquirt.

I'd stick with Bosch, but not necessarily BMW. FI systems from Bosch or Siemens are just a commodity, basically. One size fits all.

IMHO it'd be FAR easier to wire the aftermarket standalone first, get it working with the stock parts, then do the radical TB or turbo upgrades.

Mr Doricar · « **Reply #2 on:** November 21, 2010, 10:52:24 AM »

Hey Dave,

Do you know the company Dbilas in Germany? Their throttle body system comes with just a chip, so I was hoping to just use their chip instead of a standalone.

DesktopDave · « **Reply #3 on:** November 21, 2010, 04:17:52 PM »

I'd heard of them, I think there are a few members on the board with that same setup. E36 M3 bodies can fit too, with some small modifications.

Mr Doricar · « **Reply #4 on:** November 21, 2010, 04:22:21 PM »

Yeah I'm sure M3 bodies can go on OK, but here in UK bike parts are so freakin cheap its unreal. The bike throttle bodies inc injectors, fuel rail, throttle sensor and airbox is only 120 pounds. Very cheap compared to M3 parts

Brian · « **Reply #5 on:** December 13, 2010, 04:09:24 PM »

Where are you in the UK James? I know a rolling road that can do a live map then burn it onto a chip for you. Basically they drive your car on the rolling road hooked up to a laptop and change ignition advance fuel etc when the car is driving. The best power map they can get is then copied onto a blank Eprom chip, this replaces the original ECU chip and you are good to go.

Edit - Any idea how much the guy charges? I'm working on an R1 carb conversion, have had a flange made up and was going to work some manifold runners from alloy tube then get them welded, may save a lot of grief if he is able to do the manifold for a reasonable price. Cheers.