Can you do me a HUGE favor - measure your header O.D ?

Hey guys,

I bought a stock exhaust system from a guy who sent it to my US shipping address (2 hours away). He sent me an e-mail telling me that he thinks he sent a header for a CRF250R instead of my CRF450R.

I measured my broken header and came up with an inch and three quarters.

I called the people at my US shipping address and they measured the header, but I don't know what the outer diameter of a stock CRF250R header is. Could someone do me a HUGE favor and measure their stock header - like this (2 pics below) :



Stock crf250r header 1 3/4 INCH OD

The header you have in the pic is not the stock header for a crf250r but the stocker has the exact same measurement as your pic!! (or atleast it doesnt look like a stock header from your pic)

I measured my broken header and came up with an inch and three quarters.

I measured my stock header (in pics). I`ve got a 450, and the pics I posted are that of a CRF450R header. I wanted to show people how, what, where I was taking my measurement from.

I don`t have a CRF250R header to compare to, so I am asking for someone to measure their stock 250 header in the same way I`ve measured my 450 header.

Sorry for the bad blurry pic and wore out tape measure but its all i had in the trailer on short notice lol....the od is 1 3/4 inches on crf250r header


rovercrf, you`ve just earned positive gas !! Thanks for your help !

I had thought the 250`s pipe had a smaller o.d, guess I was wrong. You learn something new everyday !

Glad to help. But we still didnt solve your problem did we? You still dont know which header he shipped you? correct?

No, but he had two 250 headers and only one 450 header. Now, after shipping one out he`s got one 250 header and one 450 header. Hè doesn`t think he had 2 450 headers (before he shipped one to me).

I thought there was a difference in size (o.d) between the two headers, and that would give me confirmation that the wrong one was sent.

If there was someone who was into MX at my US shipping address then I might be able to talk to them enough to figure out any difference. But, no such luck.

Anyway, thanks again for your help !

The opposite end of the header on the crf250 is 1 1/2 inches

Same deal with the 450, 1.5" on the other end. Hmm interesting...

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