Piston Shims

[CPH Lambretta]

I am in the process of fitting a 175 kit to my standard italian DL150, I am useing the original crank which has no big end shims, so I bought a pair of 1mm piston shims from Scooter Restorations,but there is no space to fit both shims.
I can get one shim in but not both. I thought of running it with just one shim but maybe it will run wonky or taking a file to the inside of the piston and opening it out a bit?
So what do you all think,any advice?

[WINTERMODEL150]

I am in the process of fitting a 175 kit to my standard italian DL150, I am useing the original crank which has no big end shims, so I bought a pair of 1mm piston shims from Scooter Restorations,but there is no space to fit both shims.
I can get one shim in but not both. I thought of running it with just one shim but maybe it will run wonky or taking a file to the inside of the piston and opening it out a bit?
So what do you all think,any advice?

Hi,throw the shims in the bin and put it together as it don't need them

Dean

[CPH Lambretta]

How do I put it together so it doesn't need the shims ,without changeing the crank or piston :wtf:

[WINTERMODEL150]

How do I put it together so it doesn't need the shims ,without changeing the crank or piston :wtf:

Hi,if you measure the old piston you will find that its a lot wider inside where the gudgeon pin goes (for shims) opposed to the later 175 conversion style piston that's narrower thus not requiring shims allowing you to use your old crankshaft,so bin those shims you don't need them .

Hope this helps

Dean

[CPH Lambretta]

Interesting, so because the 175 piston is narrower inside I can do away with the need for piston shims. Sounds good to me,I've never used shims before.
The scooter came to me as a basket case and missing the piston/topend so I didn't have an original piston to compare the 175 piston to.
Cheers Nick