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Discussion Starter #1 (Edited)
So swapped the 1100 cams for 750 cams and it work perfectly.

The dimensional shape of the cams is exactly the same.

Things that match are:

Camjournalholder OD
Camjournal ID
Camlobe width (basecircle is the same)
Spacing between cam centers (750W and 1100W cylinderhead) is the same so the cam lobe angles are the same aswell (heard some rumors on the internet that these were different but then all the other variables wouldnt match)
Distribution timing and marks are the same
Chain length (13 pins) between the 2 cams is also the same
Camsprocket dimensions and position is the same

So in other words its a straight swap :cheers



Only thing that are different is the shape of the lobe, in other words the valves timing is different



Left cam is from the 1100W, right cam is from the 750W

The 1100W cam is more pointy then the 750W cam

750W intake cam opens earlier and closes later
750W exhaust cam opens earlier and closes the same time as the 1100W exhaust cam

One can easily see the advantages of these cam swap (cylinders get better filled with mixture, engine might climbs faster in rpm's?).

But there are some things that i noticed:

1: Valve overlap will now be greater which means the chances of pumping fresh mixture straight into the exhaust are likely, i counteracted this 'problem' by using the 750W exhaust cam which has lesser valvelift to create more backpressure (dont know if that works???).

2: Since the intake valve closes later you might have lesser compression during the lower rpm's or during a compression test.

Cold engine compression test confirmed this but i need to testrun the engine first and will meassure once my bike is setup to have a warm compression test.

I also made some singh grooves in the cyllinder head which could also lower the compression but not 3-4 bars i reckon.

Those 2 things were the first that i direclty noticed, i see no further issues for this swap.

Oh is there much difference between a cold compression test and a warm compression test?

Compression pressure readings for the cyllinder were all between 12-12.5 which is ok but hoped for a bit more.
 

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Discussion Starter #2
Started the engine today and it works perfectly!

Engine seems to run much quieter then before?

Good thing or bad thing?

I mean even the 'normal' rattles are gone (even from the alternator drive).

Guess the camchain and/or tensioner were to loose from the start.
 

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Awesome Ben, finally we can put this to bed.

Knight can you sticky this please?
 

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Many thanks
 

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Yoshi 750W Stage 3 are the same profile as Yoshi 1100W Stage 2. 750 standard cams have lower lift to suit smaller valves. I see no point in running stock 750 cams in an 1100.
 
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