Li 150 Gearbox Servetta and Innocenti

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Lamaddict
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I know there's a slight difference but what about the overall performance, is there a marked difference, which one is really best and for what reason?
rosscla
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I think the overall ratios might be similar but the jump from third to fourth is big on the Spanish 150 boxes which means you need to leather it in third to get it up into the power in fourth on a tuned engine. Probably fine in a standard engine or torquey motor but not good in tuned ones.
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Lamaddict
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Thanks Rosscla, I also have a Li125 italian box any views on that?
shocky
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Not all spanish li gearboxes have the big jump infact ive never seen one and ive stripped lots of spanish 150 engins if each gear has the same amount of teeth as the italian then they are exactly the same
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speedy
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The LI 125 gearbox is primarily used for sidecars if that helps.
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Doom Patrol
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I don't think the Spanish and Italian LI150 gearboxes are any different. That's a misconception. It's the Spanish Special that has the bad jump.
bristolmod
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Lamaddict wrote:Thanks Rosscla, I also have a Li125 italian box any views on that?
depends- is it an early one or a late one?

Early LI125 boxes were fitted to S1 S2 and early S3 125's and are good for sidecar use. Ratios 9;12;16;19 and 51;42;39;35

However, late LI125 boxes are the same as LI150 Special (Pacemaker) boxes. 11;13;17;19 and 50;41;39;35

Chris
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Lamaddict
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bristolmod wrote:
Lamaddict wrote:Thanks Rosscla, I also have a Li125 italian box any views on that?
depends- is it an early one or a late one?

Early LI125 boxes were fitted to S1 S2 and early S3 125's and are good for sidecar use. Ratios 9;12;16;19 and 51;42;39;35

However, late LI125 boxes are the same as LI150 Special (Pacemaker) boxes. 11;13;17;19 and 50;41;39;35

Chris
It's an early 125 gearbox, don't know whether that's good or bad, can't see me using a sidecar. The other Li150 gearboxes are Servetta Special ones???
Grumpy225
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The big third/fourth gear jump is on late 70's serveta 150 special. Like they said, it's a big jump but if your motor can pull it then no problem.

Early Li125 can be prone to breaking teeth (see stickys book to determine what gear box you have) but can be made to work well with the right sprockets.
Lamaddict
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Thanks Grumpy, mine is are early 70's Specials not late ones. I guess they could be the same, I'll have the engines apart some day. I did increase the front sprocket size on one and it goes well.
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