Scooterotica

Hi all, I am thinking about buying my brotherinlaws Li 225 special. My biggest reservation is the engine, or more specifically the Mugello 225 kit that's fitted to it.

The engine specs are as follows:
Sil 200 casing, Mugello 225 (not sure what model but the engine was built July 2007), AF Rayspeed 58mm crank, JL3 Pipe, Delly 30mmm PBHB carb with remote filter. It also has taffspeed clutch, IWIS chain, SKF bearings, Rolf seals, MBD chain guide & electronic ignition.

It has always had a problem with boging down badly at low throttle openings and has had the carb & exhaust changed. If you don't give it a fair few revs on take off the engine will either stall or bog down badly and take a while to start running cleanly again. Once your up and going the scoot seems to run OK, but you are always blipping the throttle at lights and it's not the nicest scoot to ride in traffic. Fuel consumption is also pretty bad.

On reading the various forums it would appear that the Mugello 225 is not a very highly regarded kit "out of the box" (and I am sure this would be basically an out of the box motor). I guess my question is - can I fix this bad low speed running without major surgery or expense (I am in Perth, Western Australia, so I can't just pop along to the local Guru as you guys in the UK can). The general opinion seems to be that you need a 60mm crank to make it work well (why is this?), together with cylinder base packing plate to alter the port timing and head machining to get the proper squish after said crank & baseplate mods.

I don't mind working on the engine myself, including things like matching ports to manifolds etc and would love to draw on the combined experience of the forum to see what solutions are available, preferably the cheaper the better. Or is the Mugello 225 a rite-off!

the 225 seems to work best with a clubman and smaller carb. ive got a clubman and 24mm mikuni on one and its a nice 12 bhp commuter but ive tried a jl3 and a kegra race pipe and found the pipes put the power further up the rev range but then the kit would not let it rev out so its a lose lose.

60mm crank improves them or have it tuned or even sell the kit and fit a rapido in its place which would go much better with the rest of the set up

Any change to barrel is going to cost you about $100 in postage alone.

Are you sure it's not a jetting problem?

Daz here from the lambretta club of south australia ,if you live in perth you can take your scooter around to mick and i am sure he can sort it out for you, just ask for his details on the plsc .asn website, if not you can contact me via the same site, i have been tuning lambrettas in Adelaide for over 25 years and do a lot of porting and high preformance engine building, i also do a lot of work for the perth lads and have a very good deal worked out with a trucking company to get scooters from perth to adelaide and back , cheers Darren.

All depends on which version of the Mugello it is. There are a number of versions of this kit, each with its own head design, compression ratio, and porting spec', with each one being better set up with X rather than Y. Until you know which version you have then we will be unable to give you much worthwhile advice on how you might better it. That said, I too would question whether this is not a result of another factor, e.g. jetting, gearing, etc.

As regards 60mm stroke... I have an early version that works wonderfully with a long stroke crank and I have a late (not current) version that has too much transfer timing as it is, which only gets worse unless you start to machine the barrel. As such, going long stroke may make things worse, rather than better.

I quite like Mugellos and don't think that they are a bad kit but you need to know what you've got and then set it up accordingly.

Adam

Thanks for all the answers so far.

I am hoping it is something as simple as jetting! (hope I have more luck with that than the Wal Philips fuel injector I had on my scooter in the 70s, never did get the hang of setting that up properly). And I guess as you said Adam, until I know exactly which version it is there can be no definitive answers (hang on, this is a scooter forum, there's no such thing as a definitive answer ), anyone know how to tell which version you have?
Hi Darren, nice to say hello and Lashspeed has a pretty good rep in the west I think!