MSefi.com read only forum (Jan.15,2018)

Hello this is my first post, I am in the construction stage of building my PCB V3 board. I have previously built and currently running Megajolt on my 1971 1400cc Triumph Spitfire. I have run 33mm DCOE carbs in the past with good results hence the idea of a 33mm Throttle body.
I am looking at a set of throttle bodies from a ZR750 (Kawazaki) these are 33mm but have 1 choke plate and 1 throttle plate per body. The choke is operated by a small motor(servo) can Megasquirt operate the electronic choke? and more importantly will these throttle bodies be suitable for my application? I have read a lot in respect of the measquirt and cannot find this has come up before?

Regards
Rob
Manchester UK.

While you can use MegaSquirt with these throttle bodies, the "choke" device is actually an auxiliary throttle body used to dampen out throttle response at low RPM. MegaSquirt will not control this, but it can be wired open or closes as appropriate. It would be better to find a set of throttle bodies without it.

A lot of folks have removed the servo throttles completely; you'll need to block the holes in the side of the housing where the acting rod went. You might look at the Yamaha R6 CV-style TBs (NOT the servo driven TBs; they are quite unusable with MS). The CV slide keeps air flow speed up even with (relatively) oversized TBs, and they are easily dismantled and respaced (the fuel rail will need some work, obviously).

DonTZ125 wrote:A lot of folks have removed the servo throttles completely; you'll need to block the holes in the side of the housing where the acting rod went. You might look at the Yamaha R6 CV-style TBs (NOT the servo driven TBs; they are quite unusable with MS). The CV slide keeps air flow speed up even with (relatively) oversized TBs, and they are easily dismantled and respaced (the fuel rail will need some work, obviously).

Thanks for the reply. I was looking at the ZR throttle bodies as they are the correct MM. The Yam 600 are 42mm arnt they? Would this not cause problems getting them to run correctly and getting the mixture right across the rev range?

Rob

The '03-04 TBs are 38mm; the '05 R6 (and '06+ R6S) TBs are 40mm. As mentioned, the CV slides will maintain the air flow velocity, improving mixing and throttle response.

DonTZ125 wrote:The '03-04 TBs are 38mm; the '05 R6 (and '06+ R6S) TBs are 40mm. As mentioned, the CV slides will maintain the air flow velocity, improving mixing and throttle response.

Thanks mate