Lambretta D125 Clutch and High Revs
Q1: When I try to engage when the engine is running I have plenty of tension at the lever and have adjusted the cable but still no joy:
Has it ever worked? Have you had the clutch out yet and are all the parts there (Nothing missing)? I would drain the oil, take the clutch out and ensure I could separate the plates with ease, put back together and try again. Also it may be worth checking one of the books on the website (Parts list) and ensure nothing is missing (All parts are there), when putting back together, if it has never worked.
If you have not already done so, please read the article on the website “how does a lambretta ld clutch work” (Or Google search online if you can’t find it with ease on the website – it should be listed at the top of Google) and maybe give it a bit of a once over.
Q2: MA19 Carb – High Revs
The MA19 carb was normally installed on a 150 Lambretta (19mm choke – jet max 100 / 100mm). The 125’s normally have a MA18 carb (18mm choke – jet max 75 / 100mm). However, the MA18’s tend to be difficult to find. The MA19 was probably installed at a later date for whatever the reason. Search online for “MA18B2, Innocenti code 00412041” for what is normally fitted on a 1951 model 125D. In November, if I get time, I will try to upload various carburettors on the website for peoples viewing on what should be installed.
Similar to above, start as close to the source as you can. Remove the throttle cable off the carb. Once warm and choke down fully (Old MA18B2 carb have a little leaver you push down), if you continue to have high revs, it may still be sticking somewhere. I would then use fresh oil and fuel, clean, try again and then review other areas such as new jet; needle position and so on. Oil may be playing a factor (New float still sticking maybe due to thick oil / too much oil in mix making float stick / oil separation from fuel depending on storage and how long for)
Also, your running a 19mm choke on what should be a 18mm choke. If your choke is still on, even slightly, you will of course have move revs, so it may also be worth looking at this area as well (Once you have bypassed the handle bars / use of throttle cable).
Let me know how you get on and if you continue to have problems, I will endeavour to go into some more possibilities.
All the best and good luck.
John