hello Ali,
Here the same , I used a hole saw (21euro) to make the holes in the TR1 crankcase !
I only have to use that /thing axle from the TR1 , the rest I can take from the BT1100, not including final drive gear of course ?
Would it be wise to use xv920 cylinder heads? can I also use no seal under the cylinder or is that too much?

What is the correct or minimum squish gap in mm ?
I am learning a lot here and I love that  

From an engineer's point of view: everything above 1mm of gap isn't a squish gap, but a squish valley.   My current XV1100 based engine come out at 1.1 and 1.25 (or there abouts) and runs notably cooler. (It was 1.6 and 1.75mm of squish before.)

Ideally you would want to aim for sub 1.00mm, as that's where the squish gap (again) becomes vastly more effective. I run an XV700 head with the small valves, so I was pretty confident about piston to valve clearance, but even then, I checked it with clay and the clearance was in the 1.5mm region, i.e. plenty. Not sure about the bigger valves. If I were you, I wouldn't chance it.

Hope this helps
Greg

If the gasket matches, you should be able to bolt it on. (I may look a bit daft, with two styles of covers, but it should work.)

That being said, you can also convert to XV1100 covers (these often go cheap), you'll only need a spacer under the generator and pickup as they would be spaced out too far to get a reliable signal.

hey Ali ,

XV1000TR1 crank with one bearing: 11.1 kg , piston with axle:0.595 kg , clutch:4 kg , flywheel: 3.2 kg

BT1100 crank with one bearing: 9.6 kg ,piston with axle: 0.495 kg , clutch 4.25 kg , flywheel : 6.4 kg

then you have to add 2 plates to the clutch of the TR1, the difference is no longer great

greetings patrick