Engine options

[gizmo]

Just acquired a bog standard gp 125 which I intend to use for work. 10 mile blast on quiet roads. Looked at other posts and sort of decided on a rt kit or rb. Needs to be reliable as possible but never used either before. Any advice appreciated. Thanks

[foremanbob]

RT kits just work... easy to build, and plenty jetting advice for a PHBH 28

The BGM clubman is perfect with them for a 4.8 final drive, or if you want an expansion I use the JL3 curly again with a 4.8 final drive.

Also look at the Rich Taylor GT kit, that comes with a reed as standard...

[burnside]

GT186 would be perfect, use mine for my daily commute (9 miles each way) plus rallies, 10k miles on it now and has been bullet proof. For rallies it will cruise at 60-65 comfortably with plenty left for overtaking.

[MickYork]

I think it's more a question of what not to go for, the RT, GT, RB, Muggello, Casa, Imola, (Quattrini ?) are all proven kits with their own followers. The cheap Indian kits are the ones to steer clear off.

All the favourites have their pro's and con's and the kit is only half of it....carb', exhaust, gearing, electrics, etc.

[Scooter Paul]

Here’s a radical option......although the GP/DL engine is a good base for a big bore conversion, nice gearbox ( same as GP200) why not stick with the standard 125 set up, maybe with a mild tune like a Scootopia 22mm carb and a quality clubman exhaust. It’s a sweet running engine that’ll last and last with regular love and attention.

[missing lynx]

I would just just get a 150 top end, 22 carb and clubman exhaust then change gearing to suit and if it's not already convert to electronic

[corrado]

Here's one I prepared earlier ...........

Small block kits.
Not sure how many small block kits there are now on the market but here's a few to go at, Gori cast iron 175 & 200, GT186 is also cast iron with reed valve. Alloy kits range from Casa 186, Mugello 186 & 200, MBbgm 195 all normally aspirated then Imola 186, Super Imola 186, RB200, Casa SS200 and Quattrini 210 which are reed valve kits. They're all good kits and probably with the exception of Indian [Ebay] 175 / 186 kits you can't buy a bad kit, only one that doesn't suit your riding style. You're better off posting the type of riding you do, what speeds, how far, and who with before buying a kit. Cast iron isn't generally as forgiving as the Nicasil lined alloy kits [opens another can of worms] but it does tend to warn you of impending doom by way of "nipping up". If a cast iron kit seizes then it's generally a case of a rebore and new [next oversize] piston, a fairly easy fix. When an alloy kit goes bang it generally doesn't seize it tends to burn a hole in the top of the piston and generally wrecks the nicasil lining. This necessitates the barrel being relined and cost of a new piston, which is much more costly. Both cast iron and alloy have their lovers and haters. The more power the kits produce means that more engine internals need replacing to cope with the extra power, mainly crankshaft and clutch. The Casa 186 kit was designed to work fine with standard crankshaft and small carb, it's probably [with the exception of the Gori 175 kit] the lowest powered [out of the box] kit. The alloy reed valve kits tend to be at the opposite end of the spectrum to the Casa 186 kit and can produce much more power [read 3 times the power of an SX200 in standard form] and like to be revved high to get the best from them. Price wise there's only about £200 difference between the Casa186 and the Quattrini 210 but you'll probably need another few hundred quids worth of upgrades to engine components for the "faster" kits. Buyer beware.

[gizmo]

Here's one I prepared earlier ...........

Small block kits.
Not sure how many small block kits there are now on the market but here's a few to go at, Gori cast iron 175 & 200, GT186 is also cast iron with reed valve. Alloy kits range from Casa 186, Mugello 186 & 200, MBbgm 195 all normally aspirated then Imola 186, Super Imola 186, RB200, Casa SS200 and Quattrini 210 which are reed valve kits. They're all good kits and probably with the exception of Indian [Ebay] 175 / 186 kits you can't buy a bad kit, only one that doesn't suit your riding style. You're better off posting the type of riding you do, what speeds, how far, and who with before buying a kit. Cast iron isn't generally as forgiving as the Nicasil lined alloy kits [opens another can of worms] but it does tend to warn you of impending doom by way of "nipping up". If a cast iron kit seizes then it's generally a case of a rebore and new [next oversize] piston, a fairly easy fix. When an alloy kit goes bang it generally doesn't seize it tends to burn a hole in the top of the piston and generally wrecks the nicasil lining. This necessitates the barrel being relined and cost of a new piston, which is much more costly. Both cast iron and alloy have their lovers and haters. The more power the kits produce means that more engine internals need replacing to cope with the extra power, mainly crankshaft and clutch. The Casa 186 kit was designed to work fine with standard crankshaft and small carb, it's probably [with the exception of the Gori 175 kit] the lowest powered [out of the box] kit. The alloy reed valve kits tend to be at the opposite end of the spectrum to the Casa 186 kit and can produce much more power [read 3 times the power of an SX200 in standard form] and like to be revved high to get the best from them. Price wise there's only about £200 difference between the Casa186 and the Quattrini 210 but you'll probably need another few hundred quids worth of upgrades to engine components for the "faster" kits. Buyer beware.

Well, after your very complete reply it would be rude not to respond I am mainly using it for short sharp blasts. 10 mile sprint to and from work and run out to daughters. Must admit the RT with an expansion is looking favourite at the moment. It sounds reliable and easily set up

[MickYork]

Just did a 200 mile round trip with a mate on an RT. Going up the A19 to Whitley Bay it was flying, 65-70 for long periods. Very impressed. Coming back he struggled to overtake lorries and the lack of power was noticeable. I assume we had a slight tail wind going and a headwind coming back.......the difference in performance was chalk and cheese, 2 different engines.

Not sure of his carb but he had a BGM V4 clubman.

[Nudger]

Here’s a radical option......although the GP/DL engine is a good base for a big bore conversion, nice gearbox ( same as GP200) why not stick with the standard 125 set up, maybe with a mild tune like a Scootopia 22mm carb and a quality clubman exhaust. It’s a sweet running engine that’ll last and last with regular love and attention.

+1

[coaster]

Here’s a radical option......although the GP/DL engine is a good base for a big bore conversion, nice gearbox ( same as GP200) why not stick with the standard 125 set up, maybe with a mild tune like a Scootopia 22mm carb and a quality clubman exhaust. It’s a sweet running engine that’ll last and last with regular love and attention.

+1

A 125 will give you a top speed of about 40-45 mph and very underwhelming acceleration, definitely no fun on dual carriageways

My personal choice would be the GT186, I have the larger 240cc version and have ridden across large parts of europe in the company of GT186's I can vouch for the fact that they can easily keep up on dual carriageways at around 60mph and cope with most hills. My GT240 runs a BGM clubman and is just like a powerful Li150 to ride, no powerband, just open the throttle in any gear and it pulls.

[Nudger]

Here’s a radical option......although the GP/DL engine is a good base for a big bore conversion, nice gearbox ( same as GP200) why not stick with the standard 125 set up, maybe with a mild tune like a Scootopia 22mm carb and a quality clubman exhaust. It’s a sweet running engine that’ll last and last with regular love and attention.

+1

A 125 will give you a top speed of about 40-45 mph and very underwhelming acceleration, definitely no fun on dual carriageways

My personal choice would be the GT186, I have the larger 240cc version and have ridden across large parts of europe in the company of GT186's I can vouch for the fact that they can easily keep up on dual carriageways at around 60mph and cope with most hills. My GT240 runs a BGM clubman and is just like a powerful Li150 to ride, no powerband, just open the throttle in any gear and it pulls.

He needs it for work...10 mile runs on quiet roads...sounds like reliable fun to me. That's the problem though, we're spoilt for choice at the moment.

[Raveydavey]

Quattrini. Every other option is playing for 2nd

[gizmo]

Quattrini. Every other option is playing for 2nd

too blooming many options, that's the trouble start off thinking of a
nice simple reliable sort of motor and always get side tracked.

[HxPaul]

Casa 185 kit.No need to change the crank or electrics or exhaust system.If the scooter uses an sh1/20 now,there is no need to change it,just change the jetting and bolt on the kit and away you go.

[Scooter Paul]

Casa 185 kit.No need to change the crank or electrics or exhaust system.If the scooter uses an sh1/20 now,there is no need to change it,just change the jetting and bolt on the kit and away you go.

Good option. I built one with a 22mm Jetex and a clubman. I raised the gearing with a 17 tooth front sprocket. Standard gearing was tried but it was far too revvy. Otherwise all stock, crank ignition etc. Was really nice to ride and was 100% reliable.

[brumtony]

47C2E5F3-4996-4060-9E9E-2BCDE50E0C51.jpeg

Quattrini, been using mine for 2 months and its awesome , drive it lazy low revs hardly ever need to change down just keeps pulling , push it into the power and its like a missile front wheel in air and hang on, driven hard i get 10 miles per litre and it sounds like a 70’s moto Xer with a tsr pipe on . Big smile factor every time i ride it

[gizmo]

47C2E5F3-4996-4060-9E9E-2BCDE50E0C51.jpeg

Quattrini, been using mine for 2 months and its awesome , drive it lazy low revs hardly ever need to change down just keeps pulling , push it into the power and its like a missile front wheel in air and hang on, driven hard i get 10 miles per litre and it sounds like a 70’s moto Xer with a tsr pipe on . Big smile factor every time i ride it

Thanks for that, I've narrowed it down to the Quattrini or Rb 20

[Solid Air]

If it's on a small block and you're stuck between the RB and Quattrini then I'm another vote for the Quattrini

Everything Brumtony wrote is spot on. There's a fair few people now with good mileage racked up on the 210. RaveyDavey is currently in Ireland on his having also done (amongst others) the Derby150, Poland and Spain. I've done those 3 also and ride it daily for work etc. I've had exhaust issues in mine (grounding and cracking) as have others. Also, I had an early kit and eventually found the combustion chamber volume was too small for how we ride our scooters, motorways and distance, compared to how the Italians seem to like their engines, short sharp shocks of speed and lots of revs. That seems to have been adjusted on later kits but check it if you go for one and the carb manifold mount is a weakness but easily fixable.

There is an FB page if you're interested for more info - Lambretta Quattrini M-210-TV Riders Group.

Good luck with your decision.

Mark

[dscscotty]

I'll come in with a vote for the RB20- road and race proven, very reliable kit, very reasonably priced, here's a few in action at 3 sisters race track
https://www.youtube.com/watch?v=Cao6xTRerHw