Fredserts

There's a new thread insert design available, but it might be overkill for our applications. Still, it's kind of interesting.

http://fredsert.com/fred2/index.html

Even available in titanium, but a bit on the pricey side.

Ken

Hi Ken, what will you use into alloy cylinders? time serts , fredserts or home made , I imagine coarse outside , and fine inside?

Ken put Timeserts in Peel's CHO head here

That's a right smart looking head Hobot! I really like painting the chambers gray.

Thanks Sid I hope Peel like's it as much. Swains put on the grey ceramic insulation coating and their black body emission coating. Std size valves but the stems are 6mm for more flow and less mass. I'll have to creep up on full power loads so expect to take head off a lot at first looked for detonation signs and I'm ham fisted w/o a torque wrench so figured the Timsert would help ease removals and holding down boost pressure lit off. Ken moved the holes to fit 920 barrel and milled the chamber edged so pistons can fit up inside with rather wider squish bands and smaller chamber. This head was lost in processing for way over a year and came back missing a hunk a hunka fin that's shows up as rough welding area. This head in stock form allowed pre-Peel Combat to out jump wheelie barred drag only Sportster, up to almost 80 mph then got out horse powered beyond that. I broke in Peel with a early 28.5 mm port factory head that completely changed my view of moderns power response and was expecting even more when I finally put on this CHO head but instead it took the scary spunk out of Peel.ie: I did not have reflexly grip bars white knuckled and press butt deep in seat to keep Peel from leaving me behind. I did not have to death grip my SV650 nor the Ninja 900. All the rest of Peel's threads in Al are Timesert backed up by Left Coast Racing chief engineer. Even so I'm gonna cable down Peel's head to cradle just in case some Ducati 1199 or SR1000 'puterized' appliance gets a wild hair they can pass Peel below like 160+ in the space allowed for it out here and maybe some famous tracks too. They have traction wheelie control by cutting power, Peel's wheelie control is simple mechanical repeater Hot Shot device I may not have to let up much to keep tire in 10% slippage grip.

marinatlas said:

Hi Ken, what will you use into alloy cylinders? time serts , fredserts or home made , I imagine coarse outside , and fine inside?

Click to expand...

I mostly use Timeserts. They are also available in oversizes for holes that already have coil inserts installed that have failed. They offer a very high quality product. Unfortunately, they are not available in some of the British thread pitches we find on our Commandos (20 and 26 tpi), so I use Recoil brand coil inserts for those situations, or just convert to SAE or metric fasteners and use Timeserts. I have made up custom inserts in high strength bronze a couple times, but its a real pain. To keep the insert OD small enough, you have to make sure the inside and outside threads are lined up, with the peaks on one lined up with the root of the other. That adds more time to the setup on the lathe, and it's easy to get it wrong. I usually screw up at least once in the process.

For Dunstall cylinders in the past, I've also made steel "top hat" inserts to go in the unthreaded holes for the base studs. They spread the load over a larger area and help with the problem of the nuts and washers digging into the alloy. I got the idea from Ron Wood, who used to do that for the cylinder head bolts. You can see his inserts in this picture.



Ken