My 1000 ccR 80 G/S was done with factory parts by the PO, and it performs better for me than my R100GS.
I dont know what the PO did with the squish, but there was a topic years ago on the old Motobins forum and the guys from 'bins stated that the low comp 1000 cc pistons worked perfectly in 800 heads, producing 37% more peak torque and 35 % more peak power, so maybe the PO just got lucky
But the gearing will have something to do with the way it responds to the throttle too..
It is twin plugged and has a Boyer Micropower ignition which included special coils. Timing was set by road test, pulling hard up a long, steep hill - you can only just see the mark so it mus be around 26 degrees. Only way to do it if you don't have a timing light and the rev counter doesn't work-------.
Airbox has two large snorkels and a Unifilter foam filter and the breather bypasses it to a catch bottle.
Jetting is as detailed in Haynes for a 32 mm carbed 1000cc bike, but I have the later, stiffer, slide return spring and the needle a bit lower.
Exhaust was a full Staintune R80 G/S system, with a balance pipe, the small G/S collector and a less restrictive OEM style muffler, but the muffler fell apart and I replaced it with a small Gletter can. Probably a mistake - it is just too small to combine acceptable noise and power , although after a bit fiddling it is just borderline with both. And it sounds horn.
It had a low first/ high fifth fitted in the box by the PO at a cost of $2600-, but that crapped out after 40,000 km and It has had a $200-Ebay stock box for the last 120,000km, I cant tell the difference in in revs so that conversion would have to be the biggest waste of money ever. But it runs very smooth, so not everyone will agree with that.
I finally managed to get the rev counter fixed a couple of weeks back , and have found out that it actually pulls well from 2300 revs in top, with a noticeable spurt around 4000 revs.
It matches my mates original old air/oil cooled GXSR750R up our test hill, and is 35 km faster at the top than my 39 hp F650 , so it does pull well.
If you do the sums the optimum carb size for a decent intake velocity on our short stroke airheads is about 29 mm - two 32mm will flow enough for 98 hp if yours is pulling well and 40 mms are crass stupidity, but being CV types they manage to perform reasonably well.
It is pissing down rain outside first decent drop for four months so time to do a bit paperwork-------.
