If your happy I wouldn't up the comp., your hitting 100 tq at 26 or 2700, thats pretty good if you get out and put on miles you will find the quality of gas ya get is less than adequate most time and there is nothing worse than fighting pinging issue's. The sheets I've seen with 777 and 10.5 comp ain't hitting much earlier than your's and I've had a lengthy discussion with a good tuner that has had a lot of guy's with pinging issues at 10.5. If all ya do is hot rod around a 30 mile radius of home go for it. I should add that the way I see it you are at stock comp. on a 103? I f so a bump in comp. would help but in my opinion I wouldn't go any higher than 10.25, I'd stay away from 10.5.and what old hippie said for gains I agree with I just got on the 10.5 comp. rant and I run andrews 54's I was shooting for 10.25 to 10.3 and ended up at 10.5 and it's to much in my NON professional opinion.

 

Pinging at heavy load and high heat would be exactly why I'm keeping the CR and the CCP low.

 

That was my point. You all ready have the 777's, so to get the the most out of them ad the head work and compression. I believe the 555's would have been better if you weren't going to do head work.

 

FM told me with my 107", tw-555 and headwork to stick with the 10.25 pistons. Higher compression makes tuning much more of a process to tweak. I took their advice.

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EDIT: Just to be clear, they did not tell me NOT to do higher compression. They were just honest about the issues and work that may be required to tune the higher compression builds (10.5 and up). It was my decision to take that as "advice" to keep it simple(r).

 

While I'm staying at 10.2 with my 54s, 777s can go to 10.5 (with compression releases). A proper tune is the key to heat/ping issues.

 

I ride quite a bit and do several long rides 1500+ annually so reliability and flexibilty of weather and gas is important. What is the easiest way to boost compression to 10.2 range*without major work? Gasket thickness? Decking the heads?

 

That'll only go so far. Mix a loaded bike with 110 degree heat, a mountain, 8000 feet of altitude, and 87 octane gas, and the best 10.5:1 tune in the world is going to detonate.

There's just too many variables to run serious compression on a bike you intend to tour on.

 

You could do a few things based on what you want out of the bike.

The TW-777, as others have said, like 10.5:1 compression. Your heads can be set up to achieve this compression. The heads will usually have some porting and texturing done to help with the air flow. A good set of heads set up to match your cam will give you some good results. You'll pick up some peak HP and fatten up your torque curve a bit with a good set of heads.

The other method would be to install some higher compression pistons. If you did this, you could bump the compression to 10.2 - 10.5. You won't pick up as much peak HP as you would with heads, but your low - mid rpm torque curve will be pretty close if not slightly higher than a 103 with heads. BTW, if your changing pistons you should be also going to a 107.

Personally, for a touring bike, I'd always go with displacement vs. heads if I had to make a choice with one or the other.

The TW-777s like 10.5 compression and head work. The "full enchalada" for the TW-777 would be a 107 at 10.5:1 and some matched up heads. That combination really puts these cams in their sweet spot.

Good luck.

PS - all of the above assumes your properly tuned

 

I did the opposite, I did headwork and a Zippers 557 cam. Stock bore left at 88". I think head work is the most important part. I have 95lbs of tourqe to the wheel.