MB RT195 Carb tuning

[leebo1974]

Hi all, I'm new to the forums,
question regards jetting etc, having just rebuilt my 1965 TV175 motor using a RT195 top end and numerous other expensive parts, I've also added a Dellorto PHBH 30mm carb & having difficulties jetting/tuning it in.

Current setting are:

Main jet 125
Pilot 55
Atomiser 264
Slide 40
Needle X7
Needle position second from the bottom,

The bike starts and ticks over not too bad but giving it a little run down street is awful very intermittent/boggy
Any suggestions appreciated.

[missing lynx]

have you asked the supplier of the kit? I take it you've put a GP crank in it also what pipe are you using and what have you set the timing at?

[leebo1974]

Hi, yes I've asked Mark, he said to start with the settings I'm currently at, the crank is a "https://www.lambrettaspares.com/spares/bgm-parts/crankshaft,-58-x-110mm,-lambretta-full-circle,-bgm/mbgm0252.html"
Pipe is an aftermarket stainless job, timing set to 17 degrees BTDC

I know I'm probably going to have to take to a dyno, MB is currently snowed under with work, I was just wondering if anyone had a similar setup.

[Norrie Bodge]

Hi all, I'm new to the forums,
question regards jetting etc, having just rebuilt my 1965 TV175 motor using a RT195 top end and numerous other expensive parts, I've also added a Dellorto PHBH 30mm carb & having difficulties jetting/tuning it in.

Current setting are:

Main jet 125
Pilot 55
Atomiser 264
Slide 40
Needle X7
Needle position second from the bottom,

The bike starts and ticks over not too bad but giving it a little run down street is awful very intermittent/boggy
Any suggestions appreciated.

1 adjustment at a time m8!
What part of the throttle opening is it boggy? Straight away upto say 1/4 throttle?
IfSo I'd start with ya pilot jet & drop it to a 53

Your low to mid setup is a bit rich using a 55-pilot - av264 atomiser & the x7 needle
That also may need changing to AV266
But as I say 1 adjustment at a time ok & do plug chops once you got rid of the boggy/4stroking m8

Good luck & keep an eye on the plug colour

[Scooterdude]

I know I'm probably going to have to take to a dyno

Why would you do that? I did that once and all it did was tell me how much power the thing was making, once back home I had to set it up myself as it was running like a bag of shite and dangerously lean. Setting up on a dyno is one thing but we ride on the road so set it up on the road, takes longer but better in the long term.

Change to a AV266 atomiser, 55 pilot x7 needle and have a play around with a half step washer and see how it goes.

(Bet that's raised a few pulses!).

[leebo1974]

Thanks for the info, Its boggy pretty much straight away, I've not been able to go beyond 1/4 throttle, I've just ordered some more jets, soon as they land I'll have a play.

1 adjustment at a time m8!
What part of the throttle opening is it boggy? Straight away upto say 1/4 throttle?
IfSo I'd start with ya pilot jet & drop it to a 53

Your low to mid setup is a bit rich using a 55-pilot - av264 atomiser & the x7 needle
That also may need changing to AV266
But as I say 1 adjustment at a time ok & do plug chops once you got rid of the boggy/4stroking m8

Good luck & keep an eye on the plug colour[/quote]

[leebo1974]

I know I'm probably going to have to take to a dyno

Why would you do that? I did that once and all it did was tell me how much power the thing was making, once back home I had to set it up myself as it was running like a bag of shite and dangerously lean. Setting up on a dyno is one thing but we ride on the road so set it up on the road, takes longer but better in the long term.

Change to a AV266 atomiser, 55 pilot x7 needle and have a play around with a half step washer and see how it goes.

(Bet that's raised a few pulses!).

Reason for doing it is as you can probably tell, I don't really know what I'm doing with regards setting the carb up correctly.

[ULC Soulagent]

My setup on S2 with 58/110 crank, same carb and bgm clubman
RT195 carb setup
Pilot 48
Choke 70
Main 118
Needle X7 top clip
Atomiser AV264
Slide 50
Float 3.5g

[Meds]

I had exactly the same issues
have a look at this
http://scooterotica.org/forum/viewtopic.php?f=9&t=36233
Paul

[leebo1974]

I had exactly the same issues
have a look at this
http://scooterotica.org/forum/viewtopic.php?f=9&t=36233
Paul

Excellent, thanks

[bluebob]

please take note of the guys advising you to up the atomiser to av 266

[holty]

i a sure you have checked, but make sure your choke is off fully, if not it will run very rich, i always make sure i have a bit of free play on the cable when switched off.

[leebo1974]

please take note of the guys advising you to up the atomiser to av 266

I've ordered a 266 to try.

[leebo1974]

i a sure you have checked, but make sure your choke is off fully, if not it will run very rich, i always make sure i have a bit of free play on the cable when switched off.

Good point, I'll check that I have the same.

[Norrie Bodge]

please take note of the guys advising you to up the atomiser to av 266

I've ordered a 266 to try.

one change at a time m8? a Bournville coloured plug is the target

keep an eye on it

[Scooterdude]

When ordering Delortto jets etc I've found Wasp performance beats everyone else hands down.

[Toddy]

When ordering Delortto jets etc I've found Wasp performance beats everyone else hands down.

+1

[leebo1974]

When ordering Delortto jets etc I've found Wasp performance beats everyone else hands down.

+1

Too late, got them off eBay & paid a premium

[Mike-Allen]

My RT 195 setup

PHBH 30
Pilot 52
Choke 70
Main 118
Needle X7 second clip down from top
Atomiser AV264
Breath sweet filter
58 x 110 Crank
BGM V3 clubman exhaust

[leebo1974]

Got the new jets, and set it to same as you guys recommended, gave the scoot a run down the street but same thing, it borks out at the same place every time,