Scooterotica

Hi Guys,

I'm considering a change over from my current PHBH 30mm to a Mikuni 30mm with Power Jet. The engine is a prototype RT190 with matched inlet manifold, and flowed transfers, now fitted with a stainless Rev Tour pipe.

The current jetting on the PHBH is:

Main 118
Idle 55
Choke 70
Atomizer AV264
Needle X13 (middle clip)
Slide 40
Air Screw 1.5 out

What I'd like to know is how this setup would map to the Mikuni as a rough starting guide. I appreciate I'll have to do some tweaking to get it spot on.

Reason for the change is to try and clean up mid range and cut down on fuel consumption whilst cruising at half throttle, then when needed the PJ will cut in and give me the extra fuel required.

Any thoughts, tips etc.... would be most welcome.

Cheers

Darrell

Darrell, would having a powerjet kit (camlam etc) fitted to your own 30 dellorto give you the results your after mate, Hicksy.

It would yes, but if it all goes horribly wrong, then I have no fail back path, and besides I'm cr@p with a drill and tap !

I doubt the PJ on the Mikuni would kick in, it wouldn't on my TS1. The Powerjet on the Dellorto would be your best bet as it'll also kick in where you want it to. I have a brand new PHBH30 fitted with a powerjet that I might be persuaded to part with

I was running a 30PHBH before on an Iron RS190. That was with an RS 44mm Clubman, I've now changed the pipe to a stainless Rev-Tour and the carb to a 30 VHSH.

Previous set up with the PHBH was: 118 main, AV266 Atomiser, X7 needle 2nd clip, Choke 70, Pilot 50, Slide 40. This was clean through mid range and a touch rich at top end. I cant comment on the TM30, but used to run a TM32 on another 190 with a JL2, the carb was never quite right even after dyno'ing.

I'd had problems with the VHSH falling off when hot and the main jet is now something around 135. I was thinking of going back to PHBH for simple enjoyment of riding it without hassle! I'd bought a powerjet off the Greek fella on Ebay with the idea of fitting it on the old Dellorto, but was waiting to see some set ups posted with powerjets fitted.

I'd be interested to know how you get on with a TM30 as it's a nice lightweight carb and has decent clearance under the panels or alternatively how the powerjet works with the PHBH if you go that route. Have nearly had it with VHSH!

Cheers Stu

You wont get much help from the power jet, but it will work well regardless

based on a few 200s I have set these carb up on I would say a good starting point would be:

20 idle
200 main
use the needle that comes with it

It should run mint

Why the Mikuni? I thought the bgm pwks's were the kiddie.I had one on my iron 200 but nipped it up so removed it but that was due to the float needle jet needed drilling out and I did adjust the float but at 6k it was kicking out 2hp more and an extra bit of torque over the phbh.May get it back on at some point but its running great with the VHST at the mo so may well leave it.

Think the way forward will be to send the PHBH carb off to Cam Lam and get them to fit the PJ and jet accordingly so things match initially, I can then dial in the carb with the help of Hippy Jerry........... this will all be done AFTER the Euro, I can live with the rich running and darker plug until then

Thanks for all the input.

Cheers Chaps,

DM

teamsequipe wrote:Think the way forward will be to send the PHBH carb off to Cam Lam and get them to fit the PJ and jet accordingly so things match initially, I can then dial in the carb with the help of Hippy Jerry........... this will all be done AFTER the Euro, I can live with the rich running and darker plug until then

Thanks for all the input.

Cheers Chaps,

DM

Mentioned the PHBH set up with the 44mm pipe set up as that revved onto nearly 9000, probably revved onto the same or a bit more than the Rev-Tour. Never tried the power jet as said but did get the Chiselspeed M-Tech box and that made a big difference. Guess any of the advance/retard/vario set ups would work just as well too.

I know the PHBH well enough with those settings and can always go back to that if I have to. Would like to know what benefits the power jet would add to this engine and pipe combo as it's quite similar to what I'm running.

Out of interest what gearing do you run with the RT and what flywheel and ignition? Mines no RT but it's timings are pretty tame, with a long rod.

What have you got inside the VHST Soosh?