Some pics of the Trevor Simpson Big Bore head kit

[Chris]

Sadly, I have some odd ball engine and this will not work with what I currently have in the Hammer MT (2-bolt head which is standard versus my 3-bolt goof-ball block). I am going to find another engine (as soon as I have the funds) to install in the Hammer so I can try this thing out!

In the meantime, I thought I would toss up a few pics. Note the huge ports, replaceable head insert for different compression rates (mine is 13:1) and the difference in piston size!

For now it is a $225 paperweight on my bench but it is worth keeping and finding a decent engine I can use it with.

[Motorrad]

Oh you just made me more pissed off at UPS... I have one sitting in a box at thieir hub store cuz they think I dont work at 2:30pm on a friday to sign for somthing...

Keep in mind when you build the motor... those domes are for stock stroke crank.... Earthsurfer can modify the domes for stroker kits.....

This will make it so you dont have to use spacers on the base gasket and throw port timing off.... if you care that much...Since Im building a motor from hell.... it matters to me.

[Chris]

You are exactly right! I am keeping the stock stroke setup for now. I will stroke it out later and will mod the button on the mill at work as a next step (this is a very cool thing and one of the reasons I wanted to go with the TS BB head setup....no bogus head shims and timing changes.....thanks for pointing that our Motorrrad). For what I do, this combined with the Dominator pipe will be about perfect (I think) The next step will be a 2mm stroked and stuffed crank and I will window the piston.

Once I am ready to go with a new block, I will do a some polishing on the exhaust port and gasket match it to the Dominator pipe. I am also going to machine out the carb and match it to the intake, and remove the stock choke mechanism and mill the billet air filter to match the carb as well (like what you did Dave). That is a very nice mod and with the little slide choke add-on, I will be set in my cooler WI climate.

There are also a few small areas in the transfer ports that could be wee bit cleaner (on the edges) and I will handle that myself before I put this head on. Overall, it is a pretty awesome piece and even without running it, I am very pleased with the quality of the TS package. Yes, it is the same price as some "high-performance complete engine assemblies" but I think that in the long run, the TS BB head setup is going to be the hot setup for me!

Oh yeah....sorry to bring this thread up and make you want to punch the UPS man!

[Chris]

Excellent news.....a friend of mine has a brand new Zenoah long block and is sending it to me!

I will finally be able to mount this bad boy up and see what t can do

[vince74]

That is great news as we will be able to see what the awsome machine can really do, as no doubt you will be posting a vid to make us all jelous Chris .
I love the finish on the head...One word, sweet!
Slight pitty about the finish of the ports but it sounds like you have it covered at work. -vince

[Chris]

The ports are nice...just a little TLC to make them better

The long block will be here next week and I can get this 1/5th MT rolling! It runs great now...can't wait to see it with the BB head and pipe in place!

[Chris]

Well, yet another update on my goofy engine saga! The long block I received would work fine if I could swap the clutch housing from the old engine to the new engine....but I can't! The original engine clutch housing is part of the block?! Not a separate piece! Argh. Even the engine covers will not fit up. Argh X2.

I am just running into too many roadblocks trying to use parts of the original engine......time for plan B!