Monza 225 - advice needed

[ducatiross]

I've just bought a scooter with a Monza 225 fitted, JL4 and 30mm Dellorto.

As I know nothing about these engines, I'd like to gather your advice and guidance on all aspects of running and maintaining them. Any tips on what to look out for, what parts to use for replacements (such as reed-valves - never had one of those either !), what goes wrong and how to avoid it etc etc would be gratefully received.

I intend to use it mainly as a bit of a track toy - enter a few street class races, a hillclimb or two, maybe a sprint, and perhaps a little road use, but no touring or long journeys - just blasting around really.

thanks

Matthew

[ArmandTanzarian]

Do you mean you know nothing about the Monza kit or nothing about Lambretta engines?

If you're a lambretta virgin then welcome to a steep learning curve, an angry wife and an empty wallet.

Buy Stickys book and it will tell all.

http://www.amazon.co.uk/Complete-Spanne ... 595&sr=8-1

If you've had lambrettas before then thye Monza kit is pretty good but everything around it will wear out faster and you'll use more fuel than a 70s muscle car. they are pretty quick though.

[ducatiross]

Sorry, I wasn't specific enough. I've had a GP225 for the last 24 years, and raced a GP205 Honda in Group 4 about 18 years ago, so I know all about how expensive these beasties can be !

So what I was looking for was specific advice or experience of the Monza kit itself. From what I've read, it's a slightly less manic version of a TS1, but I've never had one of those either, nor an engine that runs with a Reed valve.

There are a lot of posts to read and gain info on Rapido's and TS1 and RB's as well, but I couldn't find much on the Monza kit.

For instance, the previous owner did not fit the packing plate under the reed valve manifold, because it made clearance between the frame and the carb too tight, but is this the right thing to do ? Will the reeds foul the piston ? What do people think the ideal squish and timing should be ? Follow Sticky's advice or go for something different ? What typical BHP should I expect from this set up (I believe the barrel is standard with no additional tuning) - I've read that some are about 19bhp or so, but should it be any more ?

What tuning options should I consider for more power but still make it reliable and rideable ? Will sticking a TMX35 Mikuni on be a good idea or is it too big (then again, I thought reed valves were supposed to stop the problems of using a really big carb).

I'm sure there's loads more questions, but that'll do for now !

many thanks for any help, and looking forward to hearing from you Monza owners !

Matthew

[ricalnic]

Hi Matthew,

I have recently completed my Monza 225 build. she now has about 100 miles on her, must say I'm pretty pleased. I've not been too patient running in and must admit she has had a few handfuls. jetting has probably been the try and try again part for myself. mine is running on 30mm phbh and Franspeed exhaust. my gearing is too long, need to come down a bit on final drive ratio, though once in the power she would stay there all day, but you'd be going to fast for too long me thinks, so might come down a bit to make 4th a bit more user friendly.
I'll be keen to hear how well you get on with it.

rgds

[ducatiross]

Hi ricalnic

What front/rear sprockets are you using with what gearbox ? I don't know what's in mine yet (it's being delivered tonight :bouncing: ) and I need to set it up mainly for track use - it's first outing willl be at Donington in 4 weeks time, and it's only done 50 miles since it's rebuild ! So I need to get some miles on it asap to run it in a bit. I was hoping a couple of hundred would be enough to let me thrash it on track !
I'll keep you informed how it goes, and it would be good if you could do likewise. Are you using standard unleaded or super unleaded ?

Matthew

[lozmondo]

I had a Monza 200 and it was lovely.

One thing to watch is that they sometimes use a slightly shorter rubber manifold which has a dendancy to split.

[ducatiross]

Right-o here are my first thoughts after my initial ride tonight.

I’ve only been about 3 miles, but it was enough to make some things very clear :-
- It’s certainly fast enough – for now at least, until I get used to it and how to ride it. I know it’s a long time ago and memory fades, but initial impressions are that it’s as fast as my old Group 4 racer
- I’ve forgotten everything I ever knew about riding scooters and have been completely corrupted by big bikes
- The handling scared me silly – the front end was SOOOOO light, and the slightest pressure on the bars would make it and me, wobble all over the place.
- The front seems like it needs about 10 kilos of ballast and 2 or 3 steering dampers on it to keep it under control and give it some stability.
- The front brake is good, I just need to practice with it to learn how to brake strongly without locking up
- The rear brake is awful – very stiff pedal, but no braking action whatsoever. There is no way this will get through the MOT tomorrow.
- The engine is very revvy – it feels like a 500cc GP bike of the Doohan/Schwantz era – no power for ages, then all of a sudden, as the revs get high enough, it explodes and shoots off down the road.
- Gearing seems quite low, but probably haven’t gone far enough yet for a proper opinion. Certainly seems more track-biased than road-biased, which is probably good.
- The clutch is very stiff to operate, and the action is quite grabby, not smooth at all. I presume it’s because it is almost new, and has been sat in a garage for 2 years, and needs some oil and road miles to bed it in.
- The gear selection is really stiff and difficult. Selecting 1st sometimes needs two hands ! Again, it may just need some miles under it’s belt.
- There is a good deal of vibration – the footboards and seat all shake a lot, but the handlebars are not too bad.
- The carburation is a bit rich and 4-strokey low down, but once it’s into it’s powerband, it clears and seems to pull really cleanly. It’s only a 30mm Dellorto but feels bigger.
- Even though it’s no where near run in yet (only 50 miles on a new engine) it feels strong and plenty quick. Will be even better once it’s loosened up a bit.

So, gotta get it through the MOT then get some miles on it and start prepping it for the track !

Matthew

[ducatiross]

Here are some piccies :-



Body needs a bit of work, but it's fine for track action !





Gotta get some serious miles on it now !

Matthew

[coaster]

Nice Jet but you might want to think about changing those tyres before you open it up too much, S1's are only rated to 60ish MPH Get some Swalbes or similar, they will help the handling a bit too