400 pistons

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julianharty
Posts: 478
Joined: 15 May 2016 16:34
Location: High Wycombe
Location: High Wycombe Area (Bucks)

Re: 400 pistons

Post by julianharty »

I recently discovered the 350 I bought has the 400 Dart barrels and pistons, the heads seem to be standard 350 heads. When the bike behaves it pulls well, although it's hard to tell what the power actually is as the bike has other issues I've got to finish sorting out first e.g. worn rocker arms, and a problematic rear carb (I've replaced the float as that was faulty that helped). So when I eventually get the bike fettled perhaps it'll be worth testing it on a dyno... My bike does have the Sachs ignition and a hand-made S/S 2into1 (from a defunct company called Gazelle in Wales) so little is standard on this bike.

The pistons seem to be standard heron design, to be honest they looked like morini pistons from above - but I was more focused on the head which I had to helicoil for the tappet cover cap bolts. At some point I may remove the heads again and investigate.

BTW: I've no idea how long these barrels have been on the bike for, it's unlikely the seller fitted them.

PS: I'm slowing making lots of changes (ideally improvements, at least from my perspective) to this bike. I aim to bring it to Cadwell in July - you could try it there if you wish.
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