LCGB Forums

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.

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?

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.

leebo1974 wrote: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

leebo1974 wrote:
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!).

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]

Scooterdude wrote:

leebo1974 wrote:
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.

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

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

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

Excellent, thanks

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

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.

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

I've ordered a 266 to try.

holty wrote: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.

leebo1974 wrote:

bluebob wrote: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

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

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

+1

Toddy wrote:

Scooterdude wrote: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

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

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,