Is the rear silencer and center expansion chamber from a 125 compatible with a 280/250? The front pipe is 45mm diameter and the outlet from the center to rear is 30mm.

Also is the expansion chamber a silencer as well i.e. does it contain packing?

Edited October 27, 201312 yr by paul_b1

The parts cat' only lists one middle section so from that I would say it is compatible. It is a silencer with some sort of packing in it but it is all welded up so I have not seen inside. The outlet size is the same.

Edited October 28, 201312 yr by richt

when in doubt, like I am now about your answer, I would look it up on a PARTS BREAKDOWN at gasgas Spain's site, (here's the starting point for manuals... http://www.gasgasmotos.es/en/manuals.html (exploded means parts breakdowns in "exploded views" and the list part numbers. older parts breakdowns (from memory) might list all 3 models in same explode, so you could see it like this.

txt125 txt250 txt280 txt300

Part1# Part2# part2# Part3#

if numbers are same then obviously same. might depend on years for sure?

they usually list parts in a chart for what fits what, like above on some part views, or used to.

2 Yes they have packing that you can repack... they tend to fill with oil/soot, new packing is just fiberglass stuff made for silencers, don't lose the screen around the tube in the middle, I clean everything I can off the tube and screen...

Cheers! I put the wrong sizes down aswell....they are 45/28 respectively.

Had a look on the manual/parts guide and they use the same centre box and same silencer from 04 onwards.....some (not all) had a different silencer on 02/03 bikes but again had the same centre box so would presume that as long as it's the same style silencer it will be fine!