1973 360rt

A few more.

I think this cylinder is toast. Its my understanding that the port in the center is used to transfer fuel/air mix from the crankcase to the combustion chamber. I would think that by opening it up to the intake manifold there would be excess back pressure to the carb. Maybe this setup had a reed valve?

Its actually kind of funny how some of us garage mechanics become garage engineers thinking we know more that the factory guys. lol.

That ma explain the cut away of the cooling fins, to fit a block. I can always weld the center up if your suspicions are correct. What about the piston with the extra holes?

If they line up with the two intake ports then I'd guess that someone was looking to open the intake early. I would think trimming the piston skirt 2mm accomplishes the same thing only with more precision.

Thanks Crash, I'll try to run it as is after I do a complete rebuild and switch to 6 speed , you see what happens when you teach a new trick? If it has a problem with running I'll modify it. I just happen to know the operators of an aluminum forge, so I can probably cast the center section. O maybe weld it. Time will tell. As you can see this thread has been dormant for quite awhile so time don't apply to this post!

I would be interested to hear the results of running this home made setup. The stock RT is a dog so I can understand why they attempted to improve HP. The six speed will definitely be a huge improvement in get up and go. A 34mm Mikuni carb would also be a big improvement in many respects over the stock 32mm Amal .

Well the piston is new, still has all the machining all the way around with no rub and the ring is perfect. So I don't think it has been tried by anyone yet. I was wondering what size mikuni might work well with this cc. Time for some testing.

Don't go to big with the carb. This bike is designed for torque so rpm's come on slow and don't go far, probably max out around 5500 - 6000. IMO a 36mm may cause air velocity to drop far enough that it would become detrimental.

You mentioned in an earlier post about needing turn signal brackets. Here are some specs from the HUsky Club News Letters that I used to build some.

Nice Crash, I have a copy of the news letters and never saw that, looks like I should re-read them.