Scooter Tuning Tips: Lambretta & Vespa scooters - how to set up Ignition Compression Jetting Exhaust

Scooter Tuning Tips: Lambretta & Vespa scooters - how to set up Ignition Compression Jetting Exhaust
Ignition curves can be tweaked and pushed backward/forwards throughout the RPM range in the pursuit of power. Cylinder heads have endless combinations of combustion chamber design, size, shape, depth, volume, corrected, uncorrected, squish band area, squish gap, squish velocity, and so on. The manipulation of it all can be a bit like a Rubik’s cube, adjust one setting, and watch how it affects all the others. I personally find it fascinating and having owned a dyno, the main thing I learned about ALL two-stroke tuning is, the more you learn, the more you realize how much you don't know! ;)
But for those who are not familiar, or even interested in these intricacies and adjustments, for those who have shied away from even attempting to set any of these important parameters properly, I have put together a very basic guide and suggested a simple setup procedure. I can’t claim this is the ultimate setup, or that it is the most powerful setup, but the steps suggested should make it easier for scooter owners to take more responsibility for their machines, and get involved with the mechanics. So this video provides what I would outline as a ‘safe average’ that balances power, reliability, and efficiency… and that is no bad thing.
00:01 Intro
01:12 Ignition Timing
01:50 4 Star Leaded vs Unleaded
03:12 Variable Ignitions
08:36 19-21 BTDC?
09:40 Problems on dynos
11:41 Compression
14:10 What ratios?
16:40 Squish Gap
21:06 Thick gaskets are not about compression reduction!
22:30 Balance the jetting
22:56 Exhaust Stingers
27:21 Don't trust timing marks
Darrell Taylor's guide to measuring compression: www.scootering...
Amazon links to further resources…
Suggested reading:
The Complete Spanner's Manual: Lambretta Scooters: amzn.to/3qX3R1v
Haynes VESPA Service & Repair Manual: amzn.to/3rNR2aY
Haynes Vespa Scooters 1959 - 1978: amzn.to/3rPov4M
Two-stroke Performance Tuning: amzn.to/3eG8quk
Motorcycle Tuning: Two-Stroke: amzn.to/3qSUpMd
Oil:
Castrol A747 Racing Oil: amzn.to/38GfUda
Castrol ‘Power 1’ Two-stroke oil: amzn.to/3eJe3Ie
Parts:
Supergrip Lambretta 5 Plate Clutch Kit & Springs: amzn.to/3bLeK1Y
Lambretta Adjustable Rear Shock Absorber: amzn.to/3qHYOli
Lambretta Viton Engine Oil Seal Kit: amzn.to/3rKWlrw
Vespa PX/PE/T5 Viton Oil Seal Kit: amzn.to/3cA6VuX
Security:
Oxford OF802 Monster Chain & Lock 1.5m: amzn.to/3vo3Ab3
Oxford OF178 GP Chain Lock: amzn.to/3eHleAS
Oxford Products OF34 Disc Lock: amzn.to/3bLiX5M
Cleaning:
Muc-Off Clean, Protect & Lube Kit: amzn.to/2Q85n3Z
Muc-Off Cleaner, 1 Litre: amzn.to/38CX7z9
WD-40 Degreaser 500ml: amzn.to/2OS6u7o
WD-40 OIL 450ml: amzn.to/2OwV2OB
T-Cut: amzn.to/3cBKnKi
Autosol: amzn.to/3cBKnKi
Tools:
Syphon pump kit: amzn.to/3eH5TQv
5l Fuel Can: amzn.to/2Q6EjSL
Flexible funnel: amzn.to/3vq72Su
Home hobby compressor: amzn.to/3bOU756
Sealey 14 Drawer Topchest and Rollcab Combo with 239 Pcs Tool Kit: amzn.to/3rQxsuH
Gunson timing light: amzn.to/3eFd0cl
Vlog equipment:
Dragon Touch 4K Action Camera: amzn.to/3rSjhoG
GoPro HERO8 Black Bundle: amzn.to/30JVxHJ
#tuning #squish #ignition #exhaust #compressionratio #lambretta #vespa #scooter #tuning #2-stroke #scooteringmagazine #scooterist #scooterrally #howto #guide

[@jameswade4761]

Great stuff Dan. Keep em coming.

[@billsmith1545]

Great video hadn't realised timing had gone down to 17 degrees will have to reset mine from 19

[@gavinevans4711]

Really enjoyed this video, Dan.

[@drunkmunkey6969]

Thanks Gavin

[@MrCamohoj]

Great products find Dan. Wish I had seen this video before because I've stared building my own ramp and bench so at least I'll save a bit of brass 👍

[@NorthSurvival]

Hello, I have a problem, I have a Peugeot Speedfight 1 100cc that recently seized up/heat seized. It was not tuned. I then changed the cylinder, piston etc. It now starts up right away, but after a while it dies all of a sudden (as if you had turned off the key) and then I can start it right up again, this usually happens when I go over 60 km/h or uphill. When I changed the cylinder etc, I also cleaned everything thoroughly, such as the carburettor, intake, new air filter, new fuel filter (there was no fuel filter before) new spark plug. I also removed the oil pump and put a metalplate with a gasket over the hole instead, I now mix the oil directly into the gasoline. Some other info that might be important. - When I drive over 60 km/h, it starts to make a noise from the variator (CVT), it´s sounds quite a lot. - When it died, I tried to start it again while it was rolling and then it started right away, but it made a noise from the variator, like something "let go" that had been seized up, like a rubber sound, maybe from the belt. - The variator belt touches the variator cover on the inside and has grinded a cut in the metal. - In the variator, where the weights are, the belt does not go down to the bottom of the wheel. - The clutch bell had turned blue from the heat. - The place where the connecting rod attaches to the crankshaft had turned blue from heat. - There was no fuel filter on it before. But i now saw there is an internal fuel filter in the gastank, can it affect the vacuum if you now have 2 fuel filters. Please help me. Regards Andree.

[@davidblagden7894]

Nice vid Dan, Cheers 👍🏼

[@deezelbum]

Really good video Dan. I've jut rebuilt my standard Li150 with electronic ignition (set up by AF Rayspeed). Previously it ran a 22mm Jetex with an AF Clubman exhaust and never had a problem. I'm trying out an old 60's twin pipe box with a much narrower manifold and I'm getting 4 stroking with the standard airbox on but no sign of it open-mouthed. I'm probably going to put the Clubman back on but I did wonder if I could improve the 4 stroking by rejetting the carb as I do like the look and sound of the old twin pipe.

[@drunkmunkey6969]

I would think the situation could be improved yes. If the situation is resolved when you mean it off, there is the clue. Get it on a Dyno if unsure.

[@craigminister5062]

Hi mate. Great video and i need some advice of you if you could help me out. Ive got a li 150 small block engine with a 175 top end kit and clubman exhaust, but its ok on a straight flat road but laggs realy bad and struggles even in second gear gettin up a hill, can you please tell me what is needed to sort this issue out any advice would me muxh appriciated. Also where are you based? As im in forest of dean glousetershire thanks craig.

[@ericwalker2172]

Great information again Dan does the stinger tail pipe matter on a clubman such as a BGM with a 225or a195 kit on or is it just expansion pipes and what exhaust pipe would you recommend for a 225 kit with a 30 dellorto carb fitted 👍👍

[@drunkmunkey6969]

Yes, stingers matter on all pipes. But the bigger the CC, the higher the revs, and the larger the BHP figure… the more they matter. There can be a lot of heat to move on certain engine component combinations, so always worth looking at. Poor recommendation depends on whether you want clubman, or expansion… touring or race. Which 225 kit? Etc… 😎

[@ericwalker2172]

@@drunkmunkey6969 thanks For the information Dan l have a classic SX200 with a BGM 225 kit on so l want to keep a clubman pipe for the look which is a Scootopia version of the BGM expansion box pipe it seems to work very well but will it remove the heat from the top end quick enough thank you hope your new venture is successful good luck👍

[@hungdog2003]

Good stuff

[@davidfrost5093]

As always great stuff, Me and a mate are doing A 1959 Douglas , all standard with a SIP ignition, what sort of ignition timing would you go for? book states 28 degrees on the old system , we are hobbyists not tuning experts, Any advise? cannot find any videos on the really early Scoots ! Regards Dave

[@vespasandengines]

Newbie question, when we say 17deg static, does mean 17deg before tdc when at idle (say 1000-1200revs)?

[@drunkmunkey6969]

It means 17 deg BTDC for the entire Rev range

[@vespasandengines]

@@drunkmunkey6969 got you thanks!

[@RPWaggel]

GOAL! I am driving a cylinder head with corrected compression ratio of 6.3 to 1 at the moment on a Malossi 210 "old" with 57 mm crank. I can confirm the compression ratio as a very good compromise between performance and suitability in everyday life. That's one of the reasons why my old Malossi doesn't want to die. This is how the head looks like: wespenblech.square7.ch/archiv/wp-content/uploads/2019/05/wespenblech-bild-10010.jpg ... In the Beginning the corrected compression ratio was at 5,2 to 1. I had problems in the 4th gear. Too little power up to 5250 rpm. I read the Malossi operation manual and went up to 5,8 to 1. In the End I went up to 6,3 to 1.

[@meeeeeeeeeeee2]

Great video as always. Your explanations are spot on. I have a LI125 with a 42mm clubman and 22mm scootopia carb. I've put a 285 scootopia kit on it and it says to set timing at 21°. I've had problems since doing that. Should I set it to 17°?

[@drunkmunkey6969]

Yes, set to 17. Using 21 degrees static is ridiculous.

[@meeeeeeeeeeee2]

@@drunkmunkey6969 I set the timing to 17°, Dan. It's been absolutely spot on since. Thanks mate 👍

[@maxalwaysgoesbyboat7715]

uhm scooze me? YOU HAVE A 285 on a 125? i nhave the exact carb and pipe and looking for a top end kit...could this work for me? HELP[ IN CALIFORNIA!@!!!

[@exsoulagent]

@@maxalwaysgoesbyboat7715 lol, misprint I reckon 185 cc

[@marcos3ltrv6]

Intresting about stinger diameter but what about box pipes? most clubmans have 20mm tail pipes!!

[@youandme3380]

Hiya Dan, Q? eventually im wanting to make my Li into 12volt instead of the 6v what it is at the moment i will be on a budget as alot of people but am i better buying the new parts i need separately or a package were i get everything i.e. stator,cdi etc? tnx.

[@drunkmunkey6969]

Just contact a dealer like AF Rayspeed and buy the whole package. 👍

[@youandme3380]

@@drunkmunkey6969 N1 tnx

[@SauterScoots]

Need some help mate polini 177, mallossi reedvalve, phbh 28mm carb, av264 x2 needle clip, cosa 2 clutch, bgm cruciform, mallossi throttle cable for the carb, polini box exhaust, I had a ramair 62mm air filter on the carb but took it off to try and sort my problem out. It was cutting out 2nd gear etc but my step dad has setup the timing with a strobe light etc at 17 degrees exact so that's good and also blew out some of the jets and checked the gears and seems to be better also put a new spark plug in as well, it's better but when I go into 4th gear it sounds like it's going to die out, but when I pull the clutch in its fine and when I change it down to 3rd gear its fine not sure what to do. 55 pilot jet and its a 122 main jet because 125 was too rich. Any ideas that would help alot

[@drunkmunkey6969]

Clarify: Size: 28 Atomiser: AV264 Needle: X2 Main: 122 Clip: ? Pilot: ? Slide: ? Float valve: ? Fuel flow test (1 pint per minute) conducted: yes/no (result if yes)

[@craighallam4472]

8 to 1 is stock on a vespa

[@terrygolding1454]

Knows is stuff

[@Paulb901]

GR8 vids Dan - TERRIBLE sound 😢😢😢😢

[@drunkmunkey6969]

Turn up your volume...? 😂🍻

[@drunkmunkey6969]

Seriously though.... yes, lots of the early ones were problematic. Take a watch of my latest video on exhausts and see if you think it’s improved. Feedback welcome 🙏