Forum

[zippy]

Does anybody know how to tell post '56 Redditch heads from '80s/ '90s Indian clones? I've had one arrive here today, allegedly a Brit. It's certainly not pre'56 - as it doesnt have the exhaust stub sticking out. It also has a pronounced flange for the carb joint, rather than the continuous stub of the pre '56. The only marks I can find up to now is 26 N 5 stamped into the underside of the head, between the gasket face and the exhaust port. I'm thinking it's Indian.Anyone know for sure?

[Bullet Whisperer]

Not a definitive answer, but if the ports look properly finished and the edges of the cooling fins are tidy, it is probably British. The Indian ones tend to have small ports that look like they have been chiselled out around the valve guides and the valve seats will not match the ports properly, with ridges and steps between the seats and ports. The fins will have steps where their ends 'join' about halfway around the head, due to untidy casting. Also, the valve seats may stick out proud in the combustion chamber. Generally messy and poorly finished, a contributing factor to the low powers and speeds achieved by Indian built machines compared with the old British versions. Regards, Paul.

[zippy]

Thanks, It's looking more Indian... I can see daylight at the valve edge, if I look down the inlet port. looks like its had an ally weld between the valves in the chamber too. has no fins off, but the general finish is as you described.- flash at joints, minor "sink" holes from casting and a general blueness to the alloy. - Brit stuff tends to fade to grey.

[Chris Tindal]

I assume with the carb flange it's a 350 Zippy. 500's are easy, wider stud spacing for the Micarb on Indian heads, narrow studs on Redditch heads for the Amal (think it's that way round)

[zippy]

Yes chris, Spot on. 500s are a dead giveaway, This is a late 350 head plonked onto a '55 350 bottom end, - Which is only a few 100 numbers away from the knackered bottom end I already have. Luckily its the bottom end I'm interested in just now, as it appears to be complete and in good nick. But I'd like to get a positive ID on the head, then fix it, so I can barter it for something I actually need for the project.

[Mark M]

Zippy, agree with everything said so far, especially the description by Paul (BW) but there is one other thing to consider. Very late 1955 350 Bullets had a new head with a push in exhaust pipe, this is noted in passing in the Parts Book by referring to both heads separately. This head is very roughly made, it appears to be sand cast rather than die cast like the 1956 onwards version. It is also noticeably heavier than the later one. I'm working on the head from the Ebay 350 Bullet (that some of you have heard of) at the moment and I will check to see if there are any numbers on it. The big give away for an Indian head (apart from the poor quality) is the carb flange, it looks like an after thought on the Indian instead of blended in neatly on the Redditch version. If you can post a pic I can tell you! REgards, Mark

[zippy]

Thanks Mark M. You have just described my head with the afterthought flange,. it looks like an extra bit tacked onto the mould at the last minute. No blending at all. The head I'm intending to run is the one with the extended push over exhaust stub, - which looks far better IMO. I wouldn't mind an off forum chat with you about these pre '56 motors, if you are agreeable. - as there are some things I havent got my head round yet....

[Mark M]

Zippy, I'd be happy to chat, email me at trials59(AT)yahoo(DOT)co(DOT)uk Send me a pic of the head just so we can double check! REgards, Mark

[John M]

Just to confuse the issue, my English Bullet has similar numbers under the exhaust port on the cylinder head. I didn't notice any when I had the top off my Indian motor.