Hitchcocks Forum

A really basic question here: I've finally got round to getting the 1999 500 Bullet on the road - now I just need an MOT... There's noticeable exhaust blow where the exhaust pipe exits the cylinder head. There's no gasket listed in the parts book and it's just a push fit, secured in place by the bracket further down the pipe (as you all know). Is there a gasket goo to get a tight seal, do I need to push the pipe in harder, or what?

Thanks for any tips. (I'm still new to these British/Indian machines!)

Plain ordinary bathroom silicone sealer does the job. Sounds daft but it does work. Just get everything clean before you apply it.

Perfect - thanks Pete.

There is such stuff as exhaust paste for high temperature gas tight seals. I got mine from the local automotive parts shop, but I'm sure you'd also find it at Halfords or the like. I guess silicone would also work, but might peal off after a while?

you can also buy a high temp sealant used for sealing wood burning stoves, works very well.

I have used silicone for many years now and it lasts until the pipe is removed, nothing seems to do the job better, the problem lies with different expansion rates and the flexible silicone copes admirably.

Silicone, defiantly not exhaust paste

Silicon rubber for high temperature use, it is used for electrical insulation on things like the cables of soldering irons which run to over 800°F (425°C) so silicon rubber bathroom sealant, allowed to cure, will take the temperature of the exhaust. Plus it remains flexible.

I've tried the exhaust paste but 2 applications both blew out within a year..

Clean up the joint and remove carbon then apply a good smear of white or clear silicon, leave overnight to cure or risk blowing it out the joint..

If you have the hitchcocks replacement exhaust without the welded boss for the PAV pipework then suggest fitting the finned exhaust cooling ring

A bead of silicon around the exhaust port and then wang the ring tight up against the head will give extra resistance to blowing.

Also does help with preventing exhaust blueing on the first bend..

The exhaust paste does go brittle - no good if you've got a lot of play. As an aside, I quite like the look of the bluing effect on the exhaust.