Indian 1915 8 valve boardtrack racer

[dav]

Picked this up from ADVrider.

http://www.youtube.com/watch?v=TfEZyCccKTs

& they raced these back in the day!!!!

[Darwin_R65]

what an awesome bike,
i love the exposed valves, gearbox chain, etc
The bike has an exhaust system, but what's with the air holes at the head?

John

[aussie]

Oh that is SOOOOOOOOO cool. It sounds damned fine for such a vintage bike.

John - it's pretty obvious what the holes are for......to let out the flames!  

[Darwin_R65]

I had a look at the web page advertised on the video and there is a link to a board track race, interesting.

I also found another video of a similar year excelsior
With similar holes in cylinder and flames.
I assume here it's the combustion coming past the rings, perhaps the holes are to prevent pressurising the sump?
I'm curious now as to just why they ported the head and cylinder.
http://www.youtube.com/watch?v=lRTGbIX3pSY

John

[dav]

John, when i first watched the vid i was thinking "what the ...." & iam still clueless, someone on here must know why there are flames coming out of the holes.

I was also thinking on the same lines about helping release the pressure.

[Mike V]

Did these guys wear fire proof pants?! Must be hell on the inner thighs. Must be a brilliant sight on an evening ride.

[Rob Valdez 79 R65]

I've no clue.

Did these guys wear fire proof pants?! Must be hell on the inner thighs. Must be a brilliant sight on an evening ride.

Sure beats LED's under your bike!