Rapido 250 heat seize

[Arfur]

Guys I’ve heat seized my Rapido 250 twice now and the common denominator seems to be the BGM Clubman. Looks like it’s seizing on the exhaust port. When I stripped it down this time 5he slip joint to the stub was very loose I’ve lost confidence in this exhaust anyone else had this issue and what non slip/stubs exhaust is recommended

Cheers

[dscscotty]

Seen this many times on big cc (225 and over) motors, not counting any loose joints, they can gas up, as the exhaust bleed rate is not adequate,

[gerryjunior]

i used a 48 mil af clubman with the larger tail pip 1" i think on my rapido 250 , pulled cleanly through the gears , never seized it but i used to blip the throttle rather than keep it at steady revs

[MickYork]

I think the RM Clubman has a larger than average, closer to 30mm, tail pipe to avoid heat issues.

[Warkton Tornado No.1]

Rule of thumb is minimum tailpipe diameter of 25 mm for any 200 plus engine expected to be given the berries.

Manufacturers can 'cheat' as far as noise issues by having a smaller bleed. That tends to be why there can be little option than fit a muffler, even on a 'clubman' type exhaust, if it is to be used as part of a package for power enhancement. Gori have gone that route.