Norton Dominator 600 cc barrels

Joined
Feb 22, 2023
Messages
4
Country flag
Hi everyone,
I am trying to get back on the roads my Dominator 77 from 1957, but it looks that I can't use the existing barrels anymore. So I am searching for some good condition barrels or some barrels that need some work. I also need the pistons, but those can also be bought after.
This engine is exactly the same as the Dominator 99.
As I've seen on the market, the 500 cc barrels are easier to get so I am asking: is there a way to use the 500 cc barrels instead of the proper ones?
Thanks in advance!
Cheers, Breto
 
There's not only a bore difference in the 88 vs the 99/77/650, there's a stroke difference as well. You'd need to replace the crank, rods, pushrods and pistons (minimum) to suit your barrels if you changed them to a 500cc model. The 650 has a longer stroke than the 99/77, but just barely, and uses the same barrels and the same bore, so it's possible to use the barrels of a 650 on the 600 bottom end, pistons, and head (checking the usual valve-to-piston clearances etc, as usual). Mind the spigots, whichever way you go.

500cc barrels are the ones in more demand in my experience (maybe due to a 500 race class for decades?), so maybe this random moment in time you're looking may have something to do with the scarcity you're experiencing. It may just require a bit of patience (always a help anyway).

The 650 is the most robust of the three motors, so if you're going to mix and match, I'd bias my purchases toward that. IMO.
 
650 barrels also hard to find. Two weeks ago saw a Commando engine with aluminium barrel and a 90 degrees crank racing 500cc class in Denmark.
Though owner told me it had taken many years to get it running reliable.
750 Commando engines in featherbed frames are not uncommon as racers in that class.
 
Thanks a lot for your help. I'll also consider to buy the 650 barrels if I'm lucky to find them. Yeomans Motor Cycle Spares have a 600 barrel and pistons for sale but I was calling them and texting them every possible way without an answer. To be honest I am not sure how their shop is working, maybe the only way is to knock on the door in Birmingham. So still searching for the 600 or 650 barrels.
 
I forgot that '57 was right around when Norton changed from dynamo to alternator. If yours is a dynamo bike, your barrel casting will have a mounting lug for the dynamo clamp, in which case you're out of luck changing to a 650 barrel (which were all alternator), unless you also change to an alternator and magneto. Nuts...

If you've got a dynamo bike, unless you're extraordinarily lucky or patient (or both), sleeveing your old worn barrel back to standard may be the best option to get the bike back on the road in a reasonable amount of time and/or money.

Andover Norton has promised new Dominator barrels, but when that occurs, and if they will include all the variants, is anyone's guess. It has been a longstanding shortage and political issue with the ownership of the IP and drawings in legal question.
 
Norvil have had some barrels cast. I have seen them as I know the guy that is machining them. They plan to make them to fit 500, 600, & 650 dynamo & alternator. Regardless of anyone's opinion of them as a supplier, the guy who is machining them is very good so I would expect them to be fine quality wise. I haven't seen him for a months so no idea what stage they are at but may be worth asking.
 
Also remember that there are at least two different fin profiles for the 600 barrels. The earlier type look the same as the 500 ones with a large radius in the front fins. The type as fitted to later 600 & all 650 models look like Atlas & Commando barrels, with a vee profile in the front fins.
 
Hi again and thanks everyone for your advices. Since I've found some barrels with 9 fins (which means 600 or 650 as far as I know) and with the mounting lug for the dynamo (which fits because I have a dynamo) I have another question: is it a chance for those barrels to be the Dominator 7 barrels? Dominator 7 has a 500cc engine and I guess the barrels have only 8 fins.
 
Hi again and thanks everyone for your advices. Since I've found some barrels with 9 fins (which means 600 or 650 as far as I know) and with the mounting lug for the dynamo (which fits because I have a dynamo) I have another question: is it a chance for those barrels to be the Dominator 7 barrels? Dominator 7 has a 500cc engine and I guess the barrels have only 8 fins.
Yes you are right the 500 barrels have only 8 fins .
 

 
Back
Top