Standard Li150 Special Pacemaker Performance

[Lamaddict]

^ All okay with that, I would also be interested to know a jetting setting for a 20mm.
My thoughts are all around my wonderful TV175 standard performance and Daryl Taylors articles in Scoootering about a nicely set up standardish SIL200 engine. If the feedback says it's a waste of time fair enough but Innocenti put some time into the developing the barrel and gearbox etc.

[Minority]

You have to remember that the SIL GP200 engine was basically "stage 4 " tuned out of the box. Darrell also mentioned in the article how big the ports were even compared to a ts1 (width wise anyway). The 150 from Innocenti won't be to the same level of tune

[Tractorman]

Following this thread with interest as I have a recently acquired LI150 Special which came with a 20 mm carb, jetted for an SX150!! As I wanted to keep to original spec as closely as possible, I have swapped for an 18mm carb, correctly jetted for a Special. After reading some of the above comments, it would seem that I could achieve slightly better performance by running the 20 mm carb! If this is so, why would Innocenti only have put 18mm' s on the Specials? Would love to hear if anyone has experienced improved performance running a 20mm, and if so, how was it jetted!
Running a standard series 3 exhaust by the way.
Sorry Lamaddict, not wanting to hi-jack your thread, but seemed a bit daft starting a new one on same/similar topic.
N.B. Still running scoot in after piston/ring change, so not really able to just swap carbs and thrash it to see which performs best at the moment!

I was reminded by this post about my mates LI 150 Pacemaker he bought in early 1966. It came standard with a 20mm carb I can remember this because it was faster than my series 3 150 and I was determined to find out why!

[johnny650]

I have a 64 LiS150 special running an original engine and gear set as far as I know.
I have fitted a Jetex 22mm carb with 150m slide , 5899-2 Atomiser 50 pilot 106 Main jet and a standard exhaust 3% fuel/oil mix with the timing set at 19 degrees.
Mine will cruise at an indicated 55mph with some left in reserve and its hauling 17 stone

I would recommend you fit a 22mm Jetex carb with 5899-2 atomiser and 106 Main jet and advance your timing to 19 degrees and see how it performs before you spend a lot of money chasing 5mph .
Heres my old gal climbing a pretty steep hill flat out . I had to back off at an indicated 50mph when it flattens out at the top.
[youtube]https://youtu.be/8r9xn7obWss[/youtube]
Where are you based Martin20 ?

[Martin20]

I have a 64 LiS150 special running an original engine and gear set as far as I know.
I have fitted a Jetex 22mm carb with 150m slide , 5899-2 Atomiser 50 pilot 106 Main jet and a standard exhaust 3% fuel/oil mix with the timing set at 19 degrees.
Mine will cruise at an indicated 55mph with some left in reserve and its hauling 17 stone

I would recommend you fit a 22mm Jetex carb with 5899-2 atomiser and 106 Main jet and advance your timing to 19 degrees and see how it performs before you spend a lot of money chasing 5mph .
Heres my old gal climbing a pretty steep hill flat out . I had to back off at an indicated 50mph when it flattens out at the top.
[youtube]https://youtu.be/8r9xn7obWss[/youtube]

Where are you based Martin20 ?

Hi Johnny, nice vid! I live in West Yorkshire, between Huddersfield and Dewsbury, where are you?
Just got my flywheel back this afternoon from being remagnetized, along with three new Dunlop Scootsmart tyres, so looking forward to a weekend in the garage.! When all back up and running (hopefully), will try my 20mm carb to see what, if any, improvements it makes!

[johnny650]

sounds like you've got the perfect weekend lined up martin .
I'm sure that 20mm will be adequate provided everything else is spot on. let us know how you get on.

Dewsbury eh mmm I seem to remember my Company manufactured and installed all the Digital interactive Audio equipment in the Dewsbury Museum.
I used to dread getting a call from them saying one of our systems had developed a fault as I knew it would be a 520 mile round trip in a day from sunny South Somerset to troubleshoot it. arghhhh
johnny

[Timbo]

Possibly not relevant but the 125 Specials were made for the Italian market and came with a 18 mm carb....

[storkfoot]

Possibly not relevant but the 125 Specials were made for the Italian market and came with a 18 mm carb....

They were 20mm, I'm afraid.

[Timbo]

Are you sure? Not what I read up. 125's I said...

[Timbo]

Think you maybe right I owned one for a few months with 18 delly and thought I read they were made for the Italian market and came with 18. Could have been an option maybe...