requesting S3 head install/ experience Info

[Simmo737]

Gday, new to the forum and GG bikes, vvv impressed so far. My last bike was a husky te310 which is a great bike, but the gasser has really impressed so far, it's a tree knife with rocket motor very suited to SE australian conditions.

Anyone have any experience installing the S3 head? I have one that was given to me as a gift, I'm quite happy with the stock engine but am willing to experiment. any negative experiences?

Reading on trials forums, some have had issues with coolant leakage, mainly on older models, is this the case on the enduro's?

Any tips for installation? the kit I got came with no instructions what so ever, I have the shop manual, but the stock head does not appear to be a two piece unit like the S3.

I'm expecting the red and black head inserts to increase bottom end incrementally, and also effect top end with an earlier sign off, is this on the mark? This has been gauged from the small amount of info I have been able to search on this forum, and also reading other styles of head mod threads.

Is fuel economy hit badly? I'm getting 90 odd km per tank using the JD jet kit on the 36mm AS2 and 98 caltex fuel at 1000' to 3000', and would like to maintain that mileage, or close to it.

which way did it move the jetting? richer or leaner from the original heads settings?

any info would be greatly appreciated.

Cheers.