Hey guys, let's have a little fun. 
If you’ve got a story let’s hear it. 
The 240 psi motor. The year was 1975. I was 18 years old, stationed in San Diego, and the Navy paid me about $75 a week. I owned lots of cheap bikes in a short time; the trick here was to buy one with several months left before the registration expired, ride it’s wheels off, then sell it while still licensed. Presto, no re-registering required. With plenty of ships in port there was no market shortage of neither bike nor buyers. I got pretty good at this and kept trading up in size and value, saving up my money, the goal being to own a Honda 750.
Ultimately, I traded some magic beans and my life savings (
OK I made the bean part up, it was some enduro bike) and picked up a SOHC 750 that needed some work. My pals all advised against it, they figured since I didn’t know jack about motors I’d never be able to get it to run. But I was told the head gasket leaked, and how hard could THAT be to fix?
Now this bike wasn’t any old Plain Jane, it had a header, oil cooler, custom black paint, a 16” rear rim, and above all it had an RC 836 kit.
Remember, those were real hot rods for their day.
Having never worked on an engine before was not about to stop me.
I bought a manual and enlisted a car guy to help get this thing apart. That’s when I found a couple of the valves were stuck in the guides.
I got it apart and had the guides reamed and a valve job done at a local motorcycle shop, but then after buying a head gasket from RC Engineering (aluminum I think) I was broke again. I painted the block, and on the advice from my buddies baked it in the motor rewind oven at about 600 degrees for an hour to cure the paint.
Imagine my surprise when I opened the door and found the block sitting at the bottom of the sleeves!
Since I didn’t know squat about this stuff, the old Chief Machinist took pity on me and helped re-seat the sleeves back into my shiny black block. That’s when I discovered they didn’t sit flush.
Even I knew that was bad.
I had no money but did have a mill. And plenty of 'expert' advice, some of it better than other.
Now, 'Pop up' pistons were what the all knowing 20-year-old self-professed hot rodders on my ship were into, and if you didn't talk 12.5:1 you were a sissy. Just ask ‘em, they all had 14:1 small block motored hot rods back home. My piston’s domes weren’t gigantic – really wimpy, actually - and they let me know that to no end.
So I stuck the block on with one piston, and sure enough there looked to be plenty of meat needing to be chopped off the top; with help I’d get those domes sticking out yet.
I’d never seen precision measuring tools before, so one of the guys does it and tells me how much needs to go.
Under the apprehensive Chief’s supervision, we set up and fly cut the block. A LOT. Now the outer portion of the pistons were dead even with the top of the deck with this little dome sticking up. So far, so good.
Of course everybody knows you can’t have power without milling the head, right? So once again it was chip-making time. I have no idea how much came off, but I do remember the cutter almost hitting the valves before we stopped.
Finally it was time for assembly, and I got to see my first torque wrench. That part was easy, but that cam stuff was scary. There were several holes to choose from in the sprocket, that darn thing just didn’t look like the one in the pictures. After much trial and error, I got the marks lined up exactly like the book showed and buttoned it up.
When the big day came to fire it up I had plenty of on lookers. They expected to see fireworks and I wasn’t so sure they wouldn’t. The first push on the starter button promptly killed the battery and someone pronounced that the motor was seized.
Crap.
Out came the spark plugs and I jumped on the trusty kick starter, and much to my relief, with a great whooshing noise it turned over just fine. But when the plugs went back in, it was about all I could do to push that kicker down with my 125 pounds. I finally jumped down HARD and to everyone’s amazement it fired up!
Learning to kick through on a compression stroke was the key.
I later did a compression test and found it had 240 pounds of cranking pressure.
Over time I figured out the pistons were the RC 10:1 castings, and the cam was an RC #240 regrind with adjustable sprocket, a bolt in with no valve pocket machining required. Why nothing hit inside was dumb luck. But it would smoke a 900 Kawasaki around town and pull little mid-range power wheelies. It ran a 12.26 ¼ mile, got 52 mpg, and most important - I had built it myself!
