CR and MT250 Pipe Interchangeable?

Top ends can swap without issue. It might need some fab work for mounts but otherwise should work. Low pipes don't really work here in the North East for anything but motocross. Torque engineering and Bassanini did make pipes for the MT if you can find one. They pop up on Ebay once and a awhile, or put out a want ad on Mark's site to see if any of the old timers have one. Probably the best swap would be to ditch the points for a CR CDI setup.

I put an MT clutch basket in my 74 cr250, this was pre Facebook, PayPal ect…… I drove 4hrs to meet a guy on NYS thruway, drove home, went to install it and found out the Cr basket gear had straight cut gear vs the MT”s angled gear engagement….. so I drove another 4 hrs that day to buy the crank gear from the same guy…. Ahhh… vintage bikes are awesome😂…. Also had a Bassani pipe on my 76 MR 175…. First aftermarket pipe I ever bought…. That’s all I got..

Looks like a bassani to me…. But my memory is fading… Much rather have that pipe than a down pipe, down pipes get hammered… I would just remove spark arrester for Mx if you can….

Looks Bassanini to me also, regardless it isn't stock! Really clean bike for it's age too.

Looks like someone already has spent some time on setting up that bike, I see a regular VM carb, Koni shocks and it is stripped all the MT equipment.

First pass at removing the spark arrest would be just gutting the tube currently in the addition pipe that was welded on. Should be a snap ring holding it in and then a hard yank to remove. It should have a baffle somewhere in the tube and just remove it and see how it goes. Longer silencers typically give more over rev at the expense of roll on.

There is a couple different ways that folks do it but the basic design is make the hot gasses go around something so that anything burning hits packing first. So if they welded a washer in the main flow path with a small hole it'll force most of the exhaust around the baffle.

Modern ones use fine mesh screen to catch anything burning coming out the exhaust but the old school ones were more crude than that.

Pull the baffle assembly and post a picture.

I'll have to agree, it could very well be a Bassanini, but it might be a Hooker. They looked a lot like Bassanini.

Actually your probably right that it is a Hooker. The Bassanini used a different heat shield on the DS bikes as we had on our TS185 when I was a kid.

My first "race bike" was a '75 MT250 that I stripped down and put number plates on. I used it for woods and MX. For trail riding I used a Bassani up-pipe that looked very similar to yours. For MX, I had an aftermarket down-pipe. The down-pipe brought the bike alive while the up-pipe produced better low and mid torque. I used the MT cylinder with some mild porting work, slightly milled head and a bored carb. It wasn't as fast as a CR, but it would out-gun most of the Euro bikes, and it was easier to ride than a CR. Biggest problem was that it was still heavy, even with everything possible stripped off, drilled out, etc. Yours already has a CR top end, so I'm guessing it runs pretty strong.

Like above ^^
You could pull the whole spark arrestor / silencer core out and build just a straight silencer (long) core. Not a real complicated part.

Looks like a Bassani that’s had the tail end replaced with the spark arrester .
Not a Hooker ..

The exhaust manifold is larger on the MT , so use a CR manifold for the downpipe