the kinetic tfr project

So there are some issues right now with the moped. A week ago, I took off the stock exhaust. then put the stock exhaust back on. It was leaky and now there is burned oil on the outside of the head and it is not running at low rpm. It just sort of peters out.

This is the stock exhaust connection:

I put on the Proma circuit exhaust and it still doesn’t run correctly, but I didn’t really expect it to. I have not upjetted the carb and am waiting for some time next weekend to just put the Dellorto 13.13 on and re-tune from there.

It was sort of a trick putting on the Proma Circuit (which can be purchased from 50cc.nl here). It was originally designed for the Vespa mopeds like the Ciao, Grande, Bravo etc, so the mounts are slightly off. It came with no instructions, but was easy to figure out.

Here is a crude diagram I made of how the thing fits on:

It comes with the baffel part (aluminum can-looking part on the back), a clamp to hold that on, a washer, a bold, and a mounting stud.

The mounting stud screws onto a bolt that sticks out of the head.

And there is a mount on the front of the proma circuit bolts on to that:

But the mount is about 1/4 inch too long for my Kinetic and the exhaust wouldn’t go on right.

I read on line somewhere that people were banging (bending) the mount on the exhaust back to accomodate, but I thought this might snap the mount off if I screwed it up, so I just took a hack saw and a small miter box that I had and hacked off a quarter inch from the stud.

The exhaust port on the TFR’s engine was really gunked up, so I had to clean it thoroughly over and over again with carb cleaner until I thought the seal would be good.

But there was a problem with the Proma Circuit’s sleve mount. The mount was slightly too small, and I tried to slip it on forcefully, but it is such a tight fit around the engine and foot pegs that it is pretty hard to get good leverage. I decided to grind out the inside of the sleeve with a dremel tool making sure that the fileings (metal dust) were cleaned out of the exhaust before it went on.

I didn’t have to grind much at all and it slid on pretty well with a little wiggling. The large chamber at the front of the pipe butts right up against those annoying foot peg mounts. I know some people who have just cut them off. I think that I am going to do the same. The pegs are pretty useless, but the bar between them was a convenient place to run a chain through when you lock it to a bike rack.

Also, because of the size of the exhaust chamber and the placement of the foot peg mounts, I had to re-route the spark plug cable and the rear brake cable wich previously ran through the foot peg mount:

Since the rear exhaust mount on my stock exhaust was threaded and the one on the proma is not, I had to get another nut and washer to complete the mounting in the rear.

Also, since I hacked a quarter inch off the mounting stud in the front, the bolt for that was too long and met the other bolt inside the stud, so I had to add a couple washers to it (as seen in my diagram).

BTW - you may have different results than me if you are thinking about doing this to your TFR and you might wreck it or void the warranty. You knew that, right?