Lacking performance at top end

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Jackomad5
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Main scooter: LML kitted
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Hi tony

Your the not the first to suggest air leak I’ve had the engine out previously and checked for air leaks using the method you refer to, even performed a leakdown test and all pointed towards a well sealed unit.

It got me puzzled. To be honest I’ve ended up for the moment just accepting that it runs hot.

Mick i may have to try cleaning the exhaust out. I do have my suspicions that A different exhaust all together could solve some of the issues such as the top end performance
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guygrrr
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Fwiw, I’m also thinking slipping clutch.

So, you absolutely can have this problem only at high rpm. And the increased heat you describe would make sense as all the clutch is doing at that point is making a boat load of friction. Drain the oil. Does it smell burnt?

Get your self a few more clutch plates or stronger springs. Also, I don’t remember what clutches the LMLs ship with, but if it’s a 6 spring clutch get your self a 7.
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more can do, less doodoo.
Jackomad5
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Joined: Tue Jan 23, 2018 10:11 pm
Main scooter: LML kitted
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Guygrr that’s good to know, I will give that I try. I believe the LML has the seven spring I think it’s basically a p200 clutch.

I’m thinking of upping the clutch gear from 21 to 22 tooth to try and help the top end I think whilst I do that I may aswell put some new plates/springs in. Do you know if there are any signs of clutch slipping or wear that can be seen from the plates. If I remember rightly last time I had them put didn’t seem to look any different to when they were new. I remember the outter plate looking wet and the rest dry.
mick1
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might worth the cost of a dyno session
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guygrrr
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As I said, the oil will smell burnt, depending on how long the plates have been slipping. But once you’ve drained the oil it would be pretty obvious and quite pungent. Also the corks may appear black or very dark brown, and sort of glazed and shiny.

I consider plates and springs to be a pretty cheap investment.

And a word about the 22t clutch. As the Malossi is supposed to be a very revvy kit you may find that it will struggle in fourth. Not that you necessarily will have trouble, but revvy kits benefit from shorter overall gearing to get to speed. I’d encourage you to get your current set up running properly before messing with the gearing. You may be surprised. Otherwise it has the potential to really muddy the water, for instance, the clutch stops slipping but now you can’t pull 4th as it’s geared too high.

Anecdotally, I had p200 gearing in a small block, long stroke, pinasco set up. And even though I was convinced it should work, it was just not that happy in 4th gear. So strong was my conviction (read, I was being stubborn), that I messed about trying to chase it down with jetting and timing changes. Dropping down a tooth on the clutch and even running a short 4th made a world of difference! And made the bike a heap more enjoyable.

Good luck!
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more can do, less doodoo.
Jackomad5
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Posts: 16
Joined: Tue Jan 23, 2018 10:11 pm
Main scooter: LML kitted
Location: Stoke on Trent
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The scooter does seem to pull very well at the moment but i get what your saying, I will try draining the oil see how it is first of all. Part of my thinking was I had heard people talk about getting lots of over rev and that upgearing in this way could go along way to improving things in that sense aswell as hopefully helping to keep heat down with the lower rpms.

And Cheers for the help!
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