Hi Guys

Thinking aboutgetting my cylinders and heads worked, looking for advise on anyone on Sunshine Coast to do so or within Brisbane area. I am thinking of going to 106 with some CNC porting being done to heads.

Cheers

Galvo

Was a bit surprised when I had my 96 upsized to a 103 (with the stage 4 kit), in as much as I got the 96 barells back in a box!. When I asked why they did not bore out the 96 to 103? The reply was , "considering hourly rates machine shops charge, it's cheaper to just go with new barells of the right size".

Galvo, i like the S&S 107 inch barrels the best, as they have a thicker cylinder wall , but they fit stock cases, trouble with stock 103 borred out to 106 is the bore gets thinner. a thicker cylinder wall will hold its round so will seal better. but like Ando said seasoned barrels re machined is good just not if they are thinner & don't hold there round. i'd go with S&S 107 barrels & pistons & hone them with a Sunnen if possible, makes me laugh, Harleys are the best and not cheap but the dealer thinks you want cheap not the best when they do work, there hourly rate is a lot higher than a machine shop. just to work on a smiple twin. cheers

S&s sell a 106 kit and a 107 kit.

The 106 kit has been around for a while and uses s&s branded flat top pistons with unusually short piston skirts. The 106 kit without any other changes sets compression at about 10:1.

The 107 kit was only released last year. Obviously an ever so slightly larger bore but the main difference is the cp branded dome top pistons. This kit without any other changes sets compression at about 10.4:1.

I bought the 107 kit for the cp pistons as there are reports that the s&s 106 pistons have had some problems. I don't know this first-hand or know people personally that have had problems but I researched the shit out of it on USA forums where these big bore kits are common as dog fuck. The research on other big bore kits from axetell and rev performance uncovered much more serious issues at play. 

I gave strong consideration to boring the oem cylinders but when you add the cost of pistons, gaskets etc, the cost of the complete kit was not much more (I bought when the exchange rate was better). And with the s&s kit there is no concern whatsoever about cylinder wall thickness and running higher compression which obviously creates more heat (which could increase the risk on thinner and weakened cylinder bores).

I've got 3,000 kms on mine now and very happy. Doesn't use a drop of oil and after the dyno tune it's very stable and reliable in terms of fuel/temperatures/detonation, and makes lots of torque. 

interesting Fat Bat, S&S always had TRW make there piston's & Adrews make there cam's

CP good pistons.

I thought only the S&S stroker pistons had short skirts but not all just the 124 inch have very short skirt as the keep motor short to fit stock frame.

Krash you're probably right about the manufacturer of the s&s branded pistons and cams as I know they don't manufacture pistons and andrews manufactures cams for a lot of diff brands. I was very curious when they released the 107 kit. It didn't seem to make much sense given they had a 106 kit. The main diff between the kits is the move to cp pistons. 

Another thing with the s&s kits is that they advertise that they are ready to be assembled without any work. I know with my kit there would have been major issues had the engine builder not taken it to a machine shop to fine measure everything and make adjustments. The primary issue was with the piston rings.

I hate to think blokes are opening the box and assembling them on the false information of s&s that they are ok to assemble as-is out of the box.

probaly cost $ 200 to bore and torque plate hone , barrels cost more than that and also , lastly do they have to gear to check bore and piston clearance correctly , even new brought in items can be incorrect , i had brought 2 kits from states 4 years ago and both sets wernt set to correct bore clearance and picked up due to incorrect clearance ,cheers guys

Fat Bat, i won't let anyone build a motor for me unless they also do the machine work too. 

you never buy an s&s motor with out pulling it apart to check before putting it in any bike to use, i suppose u could be i would'nt

hi guys ,  had new barrels here few weeksago  to bore .005 to suit new pistons , these had never been on any engine , the worst 1 had  2.3 thou taper in it ,this isnt unuseral for new barrels as they stress relieve a little dureing maching and honeing , also the in difference in the spigot wall thickness compared to the upper barrel section can move differently , there was time when a lot of eng blocks etc after casting   were buried for years before machineing to stress relieve , seasoned barrels as Krash Kincade  has pointed out could move a lot less than new ,