This is my first post in quite some time. I have had a '69 Lightning that I purchased as a bitsa bike a few years ago and kept running as a daily rider until I went back to grad school and had to put it aside for awhile.
Now, I'm done with school and wanting to put the bike into good running order. I've decided to tear into it and do some significant redo as part of getting it in top shape. One of the things that I had always been concerned with when I had the bike running previously was that it had an incorrect tank on it (I believe the tank on it was actually a rocket 3 tank) I now have a correct tank for it and am collecting other needed parts. It had been missing the engine steady stay and while I had the tank off discovered the reason for its missing. The mounting tab on the head is broken off. I don't know if this is something that can be repaired or if I should start scouting for a good used replacement head to rebuild. (I am planning on tearing down the engine to redo the bottom end and clean the sludge trap and make sure evrything is in reasonable condition)That of course leads to the question of whether I am better off converting to a single carb head and doing away with some of the headaches of having the dual carbs. The existing carbs are not in great shape and at the least will need to be resleeved. I am not interested in achieving maximum speed out of this bike and am more interested in fuel economy and reliability. At the risk of starting a huge debate I was wondering about the pros and cons of converting a lightning to a thunderbolt.
Thanks in Advance,
1969 BSA Lightning "Penelope" 1978 BMW R80/7 "Freyja"
if you are not looking for performance or correctness and you are looking for a more troublefree ride then you are on the right track.The only downside I can see is the sidecovers for the twin carb head might leave a bit of a gap . I rode mine like that for several seasons and really enjoyed it .I'd definitely recomend the stock 928 carb .the bike will have a different personality but it sounds like what you are after .
I've often thought about it; seems like I always have A65s with dual-carb heads even though I'd be just as happy with a single carb.
I've got a single-carb head sitting on the shelf, and it would be easy to rejet one of my carb bodies for it, and just use it on the Firebird. No more having to sync carbs, and do everything twice, etc.
But I've never gone to the trouble. To be honest, a properly sorted set of Amals with sleeves will last a long time (been 30,000+ miles so far and still starting and idling easy). And I guess I do sort of like that little bit of top-end "kick" that you get on a dual-carb bike; and two carbs aren't really that much trouble.
But if you need a new head anyhow, and have to source one, NOW would certainly be the time to convert. Just make sure you get the right size carb and jet it right.
It should be fun "getting back into" the old bikes!
I'm like super lazy today. It's like normal lazy, but I'm wearing a cape.
Re: Convert a Dual Carb to Single Carb???
#402588 11/08/111:06 am11/08/111:06 am
hi..i have a 1968 A65 bitsa...it has lightning frame and engine but the box of bits had a single carb head ..i put an AMAL 928 on it and i really love it...not as fast as my T120 but really tractable and easy to tune....