Wednesday, February 6, 2019

Need more power - D1 Bantam gains 25cc

Bantam in oily rag / barn find / cosmetically challenged /
disgraceful / knackered (take your pick) condition.

The nostalgia trip that is my D1 Bantam (passed my test on it when I was 17 and still have it nearly 30 years later..) went out for a test ride today to showcase a few improvements.

I've finally gotten around to properly re-wiring it following the fitment of the Electrexworld alternator and CDI ignition system. All seems good there and the bike holds charge on full beam so no problem. I changed to LED bulbs on the brake light whilst I was in the fettling mood as it regularly blew the old style ones that were there before. I decided to keep it on 6 volts though as I am too mean to fork out for a new battery and bulbs!

Having started to use the bike I again I proved the old adage of 'nostalgia, it's not what it used to be' as I discovered the Bantam to be somewhat tedious to ride with little power and gear ratios way too widely spaced. I'm sure the extra pounds I carry now over 17 year old me are not helping either.

Back when I was using the bike first time around I tried out a 'big bore kit' - ie I fitted the barrel and piston from a 150cc D3 model. Alas inexperienced 17 year old me did not change the jetting at the same time and I soon seized it up. Just recently I dug the barrel out of the spares box, sourced a new piston and a suitable D3 carb. The barrel was treated to a quick hone and on it all went.

The results are very satisfactory, the little bit extra power is enough to overcome the wring the neck out of it in second, try third, get bogged down, back to second, wring it again and repeat nature of the 125cc experience when it hit a slight incline.

So, workshop time well spent though obviously it is still no road burner. And despite the extra thirty years of experience I still managed to nip it up again on a long hill as I got carried away with the mighty power of those extra 25 ceecees. It might just be that the Tod head fitted makes it run a bit hotter so perhaps I should revert to standard for a little while. Must now remember to run it in carefully....

Extra power means I can now haul luggage so I fitted a Craven
rack. The copper pipe fixing is just temporary - I ran out of
suitable tubing.

Extra power means that I now have bragging
rights to display a cock of brass.

Aforementioned cockerel was picked up at a flea market a
 few years back but I never got round to fitting it until now.

Hills like this now hold no fear. At least they won't when
properly run in...

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