Hi PropTP, et al,
I reveal my lack of knowledge Your bike is a TT, i have almost no docs on them.
Fact is there is just too much, i can't / don't want to go there. Rather we should be able to find our way around the bikes we own.

To that end i'll correct a few of my mistakes and just start the 5th gear mod. I think that the whole job should have a dedicated thread, and i'll take a while to get that done. Very busy right now.

The 5 changes i talked about: the change in transmission ratio would have had a beneficial effect on life. Engineering principles. The 2JT gears used from 3AJ right up to the 660 3YF probably did too.

But the final mod, which now looks likely to have been most effective, was the adoption of 660 gears.

The clutch cable move had nothing to do with it, happened to be changed for 660 and adopted for 600. Seems logical.

I missed that. I found it difficult to make that connection because i never found a part list 1st 660.

Looking at the 600E part lists available right here, both 3TB and 4PT in various markets it is beyond us to find each change. The 4PT transmission has many 3YF parts. The entire case is 4PT, as is the shift drum and shift forks.

So my mod will be to a 2KF, very similar to later 3TBs and 600s sold in USA.

This has been done before. I have no doubt David Lambeth has been doing something like this for a long time. Probably perfected it, with all the experience he has.

Here, if i get it right, are photos of the gears. Plain to see they are wider, 11.2 mm to 14mm for pinion.

p

Attached Thumbnails

 

 

I am a bit confused about the oil pump. The parts list I looked at showed the 3AJ pump used in the 84,85,86 motor a 1VJ in the 89 motor and the 90,91 shows the 3AJ again. If the oil volume increased as said why is the pump the same in the 90 as the 85? The odd man out is the 89 with the 1VJ. Even though the 3AJ is the same the part number differs several times. 86-88 3AJ-99999-01858-00, 90 3AJ is 99999-02120-00, and the 89 and 91 3AJ shows 99999-02117-00. WTF! THUMPTHUMP