Topic: what pistons do you recomend for 103? (Read 822 times)

panhead1 · « **on:** July 09, 2010, 10:21:41 PM »

Got an 06 seuc with tw5 cams, rinehart true duels and tts. Tore the bike down and have play in my pistons so going to replace them. Trying to see what you guys are running and what pistons work well with that set up. Trying to decide if i want to go to the 10 to1 or just a 9.5 to 1 and what brand you run. Didnt' know if the se one are alright or if its better to go the je way. And maybe what else i should do or change while i am there. dont really feel like ripping it apart for the 4th time in a week.

Sklywag · « **Reply #1 on:** July 09, 2010, 10:45:13 PM »

Contact Brad at Yuill Bros in Reno, NV. Brad makes a great set of pistons. Coated skirts, anti scuff and coated top to keep the heat in the chamber for efficiency. They work very well & if the cylinder is honed properly to fit them correctly they are exceptional pistons.

http://www.yuillbros.com/

HD Street Performance · « **Reply #2 on:** July 10, 2010, 12:23:26 AM »

The 5 likes about a high 9/1
The factory flatop is not there and the HD 10.5 piston (obsolete) not there either.
Consider a KB 10.5 cast piston (sets up tight at .001) and with the 98cc head this piston will be right at home with your motor combo and run tight and seal well.

panhead1 · « **Reply #3 on:** July 10, 2010, 02:56:48 AM »

So what would the final compression be around with the 10.5 to 1? I don't want to get to high. I do a lot of traveling and can't always get good gas in the middle of no where. Not sure what cc ratio they are getting thier 10.5 on. Do you still run the .45 gaskets or run the .30? Wasn't sure if i should get the 10 to 1 and run the .30 gaskets. I don't need a power house just something that runs well but will last a long time and doesn't mind long days of riding.

HD Street Performance · « **Reply #4 on:** July 10, 2010, 09:09:47 AM »

Well I got into the catalog and KB no longer offers a HC cast piston for the 103"

So on to plan B
You have a 98cc chamber with relatively no squish area and live in a HOT climate. So let's talk conservative.
We target a 9.1/1 corrected for cam compression ratio or ~9.7/1 static

To get there
1. Use a .030hg
2. Light mill to heads to get down to 96cc
3. Purchase Wiseco piston kit pt #VT2756 (.010 OS)
NOTE: These pistons are 10.5/1 with the stock 88" head but with the 103 SE head will come right in line with the target
4. Bore and hone with torque plates and proper piston fit

Tuned right this will run great and be reliable as heck.

Author Topic: what pistons do you recomend for 103? (Read 822 times)

panhead1

what pistons do you recomend for 103?

Sklywag

Re: what pistons do you recomend for 103?

HD Street Performance

Re: what pistons do you recomend for 103?

panhead1

Re: what pistons do you recomend for 103?

HD Street Performance

Re: what pistons do you recomend for 103?