Whether to match LML cases to Pinasco 177?
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Enthusiast
Molested & Abused 2003 Stella 2T
Joined: 12 Sep 2015
Posts: 64
Location: Madtown
Mon Apr 29, 2019 5:03 am quote
I split open my spare LML engine this weekend to replace the shifting cross. This engine has a Pinasco 177 kit on it, racing crank, and will run a pre-mix 30mm PHBH carb with v-force reeds and a custom reed manifold from Hot Rod Scooters. (My other engine has the Malossi 166 and runs the stock oil injection with a 24mm carb; I am very impressed with the 166 kit).

I noticed that the Pinasco cylinder doesn't match up perfectly with the LML ports in the case. The photo shows the case intruding into the cylinder (arrow on bottom). Also, the skirt of the cylinder (horizontal line on top) covers up a bit of the original port in the case.

What does the group think about whether it is worth grinding away a bit of material (on the cases and on the cylinder skirt??) to match the openings? Since the cases are apart this wouldn't be too hard. On the other hand I don't want to f*** up the cases or to make my life otherwise difficult in the future (say, if I want to run a Malossi kit instead).

I would appreciate any thoughts on the risk-reward calculation, and also any technical advice as to how to proceed.

Cheers,

Jason

IMG_6099.JPG

Hooked
1997 T5 Classic
Joined: 26 Dec 2008
Posts: 186
Location: Durham UK
Mon Apr 29, 2019 5:29 am quote
Looking at prices on ebay an LML case is £150 still from india. (I use enfieldparts, there OK) so if you have the funds why not buy a spare incase?

Open the ports on yours then you have the spare if you want to go a different direction?

Are pincasso cylinders coated like t5 ones etc? I know with T5 nikasil ones, you have to be careful about damaging the plating on the cylinder walls?
Enthusiast
Molested & Abused 2003 Stella 2T
Joined: 12 Sep 2015
Posts: 64
Location: Madtown
Mon Apr 29, 2019 7:38 am quote
The LML cases from India are indeed cheap. I had no idea. <$200, shipping included, for one with bearings and mounts already installed. I wonder if the quality is good. My spare engine came from a wrecked 2012 Stella, and the casting of the cylinder head on the stock cylinder was abysmal.

Assuming I do match the current ones, would I grind away the cylinder skirt too? Is that part of matching the cases? Or would I only grind away the case portion indicated by the arrow?
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2220
Location: Chicago. Well, Evanston, but that's almost Chicago
Mon Apr 29, 2019 10:46 am quote
You will be glad you ported if you do.

If you have the tools (a Dremel with a flexible shaft, plus some grinding bits and sanding drums), it's really straightforward, especially if you're not doing anything aggressive, just matching the ports.

I documented my first porting efforts a few years back in my Porting 101 thread, which in turn drew heavily from blake7even's Sprint Sleeper thread. With that ported DR, I got 16 HP out of that build using the LML reed block and a 24/24.

I now make sure that my port timings are where I want them to be before I match the cases and fire up the Dremel. With a similar parts list (I went BGM 177 for my cylinder and a P200 60mm bell crank) to what you have, I get about 25 HP out of my LML motor.

This is a topic that myself and many others on here will happily help out on if you want to post pictures of planned changes, etc.
Member
VBA
Joined: 06 Jan 2019
Posts: 40
Location: Geelong, Australia
Mon Apr 29, 2019 1:20 pm quote
Chandlerman, do you put your crank, bearings, and piston in to work out your port timing, then pull it all apart for porting? The shop I bought my parts from did me a ďfavourĒ and installed the crank for me. Now Iím worried itíll make porting all the more difficult.
The pinasco cylinder ports are not a good match to the lml, burg the cases and cylinder need a fair bit removed to match them.
Ossessionato
05 Stella, '62 VBB, 76 Sprint V, 63 GL
Joined: 16 Jun 2011
Posts: 2220
Location: Chicago. Well, Evanston, but that's almost Chicago
Mon Apr 29, 2019 2:26 pm quote
I install it all, do all my measurement and marking, then pull it back out again to do the actualy porting work. Once the cases are marked for alignment and you know what base gasket you're using, you can just bolt the jug on to each case half and do your port matching. Once it's good-to-go, I'll install seals and then build it for real.

Having the correct tools for everything (crank remover & installer, bearing pullers, etc.) make a big difference in what you view as an "easy" versus "hard" task, too. Also, the PX (and hence, LML) motor design is much friendlier for splitting the cases than earlier motors.
Enthusiast
Molested & Abused 2003 Stella 2T
Joined: 12 Sep 2015
Posts: 64
Location: Madtown
Tue Apr 30, 2019 5:51 am quote
So which of the off-the-shelf kits match up best out of the box to the LML cases?
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