Starter Solenoid for '75 Norton 850 Commando.

Today, I had a friend of my son, look at my bike and try to figure out why I'm killing batteries on my 1975 Norton 850 Commando MKIII, and after doing some electrical checking, he said that I need a new solenoid, at the least.

I've had this bike for almost three months, and I've not been able to start it with the electric starter, or the kick start.

The plugs look very rich (I will replace them tomorrow), and after looking into the cylinders, they were flooded... Noah style.

I live in Phoenix, AZ, and I was wondering if anyone on the forum could point me to a place that I might buy a new solenoid?

Any help would be appreciated.

Rocketdoc, The original commando electric starts were notoriously poor and would seldom start a bike from cold, There are now aftermarket and modified starter motors that are much better as well as kits to upgrade the standard starter to 4 pole operation. However your real problem is why the bike will not start on the kickstarter, a well set up Norton will normally start on the 2nd or 3rd kick, I recommend that you concentrate on the timing, fuel mixture and all the other basic settings and get the beast running and starting properly before spending endless amounts of money on trying to repair a standard starter motor.

Seconded, get it to start on the kicker first, you may then not need anything on the ES side but the solenoid.

Trebled, i had a similar problem with my '73, kickstart only, i looked at everything, coils, plugs, leads, battery it came down to the critical adjustment between the pilot air screw and the idle screw.

A common modification is to replace the (original) Prestolite solenoid with any similar car type item.

Example:
http://www.vehicle-wiring-products.co.u ... /33503.jpg

But as others have already said the problem would seem to be elsewhere if it won't start on the kickstart either?

And what might those alternatives be?

Although the bike is essentially original, I've already bought a twin Mikuni carb setup and a Boyer Electronic Ignition System, but I don't have a source of parts, original or aftermarket.

Sory I don't have any info on the specific replacement types. It may just be a case of taking the original solenoid to your friendly auto parts store and comparing it with what they have?

Others here may have more information on what part may be a suitable replacement.

Rocketdock, There are lots of Norton parts suppliers both in the US and overseas, in fact I think it is fair to say that the parts situation for any of the popular British classic bikes is far superior today than when they were actually in production. I have had very happy results from 'Rabers parts mart' in San Jose, they have a web-site and I have seen others on this site recomend them, 'Norvil motorcycles' and 'RGM' in the UK (both with dedicated web-sites) have a very comprehensive supply of parts, RGM are a little cheaper but Norvil have some excelent products that others do not carry.
Although this will probably provoke a fight to the death from some of my fellow Norton enthusiasts, fitting an electonic ignition is in my opinion a good idea although your bike should also run perfectly well with points. I would advise getting the bike starting and running properly before fitting your aftermarket carbs and ignition system. There is nothing as much fun as a well sorted Norton and nothing gives as much grief as a recalcitrant one. You mentioned in your earlier post that the cylinders were full of fuel after trying to start it on this item I would check that the fuel float valves are not leaking. You could easily flood a Norton when trying to start but the amount of fuel you described seems to me more than would be drawn in just by trying to start. Good luck

Rocketdoc,
Are you running twin Mikuni's now? If so, I'd say the problem is likely the jetting. I have these on my 850 cafe racer and while they flow good air and make power, they can be tricky to get the the jetting perfect. I prefer sleeved concentrics for a reliable daily rider.

Ron L said:

Rocketdoc,
Are you running twin Mikuni's now? If so, I'd say the problem is likely the jetting. I have these on my 850 cafe racer and while they flow good air and make power, they can be tricky to get the the jetting perfect. I prefer sleeved concentrics for a reliable daily rider.

Click to expand...

This place is fantastic... and I'll do my part by trying to be smarter and look more on the Web.

I'll take the solenoid off and visit some auto parts stores and look for something similar.

I will concentrate on getting the the thing running well by kick starting first (I have a bad right leg from some earlier motorcycle excapades, and if I can't get that worked out, I'll probably have to sell it and get a new 961 [just sent my $500 deposit on a contract]).

I don't have the Mikuni's on it yet, and I hope to get it running well on the Amals first.

Thank you all again.

Just an update on my travails on my 850 MkIII.

I replaced the solenoid, put on the twin Mikuni's (supplied aitfilters will not fit, so I'm buying some foam filters), bought a new battery, plugs, and the bike started on the first turn of the crank (with the starter).

I haven't done anything with the jetting, but it idles well (~900).

Then because of the inability to shift gears, went into the gearbox, and found that the shifter return spring had fractured and was useless.

I've ordered quite a few geaarbox parts from Raber's, and hopefully, I'll be riding it soon.

BTW, the gaskets were "inside" the gearbox case. and there was no oil in it.

Again, thanks for being such a great source of information; I'm learning.