new member intro

hi,
just wanted to introduce myself and prepare you for the onslaught of questions which you will find ridiculously obvious and simple.

don't worry, i'm familiar w/ the "search" button

i am completely new to vintage bikes although my daily driver is a '73 also... (just like the commando i picked up yesterday), so i'm no stranger to maintenance and constant fixups. time will tell whether i'll be able to keep up to date on both vehicles, but i will sure as hell try.

well, wouldn't you know it, first welcome is a no-start and i'm gearing up to handle the wet-sump issue. the bike does not appear to have a choke, unless it's somewhere hidden in its nether regions.

first of many stupid questions: i haven't received the rest of the stuff from the p/o yet, mainly all the manuals and other literature. so, as a total newbie, i don't even know which is the drain fitting that i should mess with. anyone has a pic or a decent description on how to make sure i'm attacking the right one? i have plenty of tools i use to work on my car, will i need something specific, rare, and unobtainium to do this task?

thanks,
dave.

edit: one more thing... obviously, i have been unsuccessful in kickstarting it after a week or so in transit, but with some assistance i was also trying to pushstart it which did not work either. while pushstarting, i was trying it out in whatever gear i clicked into, would it have helped if i was in a specific (1st?) gear?

newbe

Welcome to the world of Commandos.

First let us know if your newly acquired Commando is a 750 or 850. 1973 was the only year both were in production at the same time.

If by drain, you're trying to drain the engine sump - the 750 has a small hex head bolt at the bottom of the crankcase. Unscrew it and keep a catch basin in place. The oil can be returned to the oil tank filler under the seat. An 850 has a larger sump screen setup that also will unscrew.

Starting is a ritual all Commando owners learn. It's not really necessary to have chokes (we are talking original Amal carbs - right). There is a plunger on the outward portion of each carb (tickler). Push down on both carbs until a spurt of gas comes out. Ignition on, push on the start arm until you feel compression then put all your weight on the start arm pushing through a complete arc. Don't be wimpy or it'll bite you. If it doesn't start in half a dozen kicks, tickle the carbs again and continue. If this still doesn't work, you may have flooded it. Open the throttle wide open and kick a few more times. Again not starting, pull the plugs, connect the plug wires while grounding the plugs on the cylinder head. Ignition on, kick start through and see if there is a spark at the plugs, then let us know what happened.

Welcome!

Hi Dave,

Welcome to the forum.

Jerry

david and jerry,
thanks for the help and welcome.

the bike is a 750, and it has a single 34mm mikuni carb. (ok, no laughing) but i'm not sure about any ticklers. are they specific to stock/oem/original carbs or do others have them as well?

also, since the sump got flooded, is there any "drying out" process that i should undertake after draining it or can i start (and hope) on firing it up as soon as i return the oil to the tank?

my car has weber carbs and i have to feather the throttle a bit to get it to fire up, should i be doing the same w/ the bike?

Mikunis don't have ticklers or chokes. they do have low speed enrichener that works as a choke. There should be a lever on the left side of the engine side of carb. Push down to activate it. Pull up for normal running.
Mikunis usually will not start without activating this.

As David mentioned, I would pull both plugs, clean them and make sure each side is getting spark. Reinstall and have a go.

Mikunis should start easy. Turn on gas, allow time for bowel to fill, turn on key, verify battery strength by activating horn or lights, activate enrichener and kick, NO THROTTLE till it fires.

Good luck.

mike,
by making it sound so easy you have actually given me hope on being able to hear it run today... can't wait until i get out of work now!

thanks

with the wet sump issue just drain the oil and refill the tank with clean oil and as a tip i was recently given when filling the tank fill about 1/2 to 2/3 between low and high. the wet sump problem could also be contributing to the hard starting as with all that oil in and around the crank it will slow the crank rotation, and cause the pistons and crank not to go up and down enough to let the bike fire. i had the same prob with starting and narrowed it down to the oil in the sump causing that problem. also welcome to the forums they are very helful at troublesome times.

regards Julian.

a hopeful update...

following some of your suggestions, i drained the sump, cleaned the plugs (prolly didn't need to), pushed the carb lever down, and 3 kicks later, it fired up.

great sound. first time i heard a norton in person. i feel like i made the right choice in passing up on *another* sportbike :roll:

now for some help, once i get it running, how long should i keep the carb lever down? taking it for a 5 min spin to get some gas, it died at a red light, and that's w/ the lever still down. was that not enough time?

also it would die when i flipped on the lights (this was at night :wink: ). i've only dealt w/ older bosh electricals and lucas, the lord of darkness himself, was the butt of our jokes. is this personal payback or will the electrics really live up to every stereotype? :?

after the initial kickstart in the garage, i wasn't able to fire it up at all. only bump start got it going. any ideas?

thanks.

Mike B.....

allow time for bowel to fill

Click to expand...

Would you indeed do that to your poor Mikuni?

Ride Safe!!!!

Dave,
do you have points or electronic ignition? and how old is the battery? two coils, headlight?? there are SO many upgrades , especially in electronics, almost afraid to ask what you have.. like a battery eliminator??? suggest you read deep into the forum and check these out - http://www.britcycle.com/Manuals/BoyerT ... ooting.htm

http://www.oldbritts.com/ob_start.html

and Reg's tips of coarse! http://users.bigpond.net.au/nortonfan/tips.htm

oh and try 2nd for push starting and you can pull up the choke lever as soon as it wants to idle without it or half way down your block.. most likey at the red light was WAY too long....

There's the Nations Capital Nortons Owners Club for you join and really feed your new addiction... http://www.ncno.org/

Your going to have ALOT of fun }{arlequin!

Let us know how it goes and regards Chris

thanks chris, i'm in washington d.c.

since i've only had it 2 days, i haven't had a chance to go through it all, but here are the electrical specs as given to me by the p/o

"Boyer Branson ignition
Sparx 3 phase 210 watt altenator/regulator/rectifier kit ,(never a dead battery, very hot spark)
Dual-lead high-output Boyer coil "


none of this has been verified by me but i have no real reason to doubt what i've been told...

You do have the right stuff there! Did it sit long before you got it?

i don't think it sat too long though the owner said he lately hasn't had a chance to ride it which is why he decided to let it go... i'm assuming he rode it to the shipper before he sent it my way... it was in transit for a week, fired up after i drained the sump, but then wouldn't fire up again, only with a push

does the ignition spec mean that the points are outta there? i remember setting my points gap on my car many times, strangely it was always in the rain :roll:
eventually i replaced them w/ a pertronix ignitor though i still carry spare points in the trunk just in case.

i will have to read up on what makes the boyer system an upgrade.

not sure on the jetting of the mikuni, i guess there is a chance it was set up for top end which *could* possibly lead to an unhappy idle

i'm getting a feeling that the seller was somewhat disappointed that the bike went to a complete greenie. in his email he stated he assumed i'd be "waaay into older bikes". i have no problem with learning this stuff but he hasn't responded to any emails since he shipped the bike. i'd like to know the detailed specs on it WITHOUT having to take it all apart just to find out.

a question ab operating the mikuni:
if i keep kicking it numerous (10+) times, is there a point of diminishing return? does the system get flooded w/ too much gas? does opening the throttle help drain the gas?

sorry for all the questions

10 times is way too many kicks. with that roman candle to the moon ignition system you have, should start first time (after a primeing kick thru) every time. Yes, NO POINTS with the Boyer..
Was thinken a gummed jet maybe if it was sitting long time but doesn't sound like that..
forget PO, he's heart broken... ) and you have us now...

spark or gas ALWAYS one of those two.. so maybe you need to pull carb and rod and spray out idle jet? have you checked your filters..
tanks rust and that fills up filters fast both pepcocks should have filters on them internal in tank.. do you have a outside line filter as well?
the transport may have shaken things up in tank or a wire connection loose ... did you load fresh gas?

good pointers, thanks. i'll take a look and see what types of filters are in there. half the time i'm not exactly sure (yet) what i'm looking at... i'll take a pic when i get home and maybe someone can help me id what is in there.

it's like hitting the crack pipe... i'm dying to ride it again. the noise alone is worth the price of admission

you sure have your head on straight !!

did you eBay this? if so maybe link is still active and we can read about and look it over..

Dave,


1. Low speed enrichener will cause plugs to foul if left on to long. It is not a true choke, it is dumping excessive fuel in the idle circuit. Release as soon as possible. It is better to use throttle for fast idle.

2. Engine dies with headlight is sign of weak battery and poor charging.
First of all, Boyer draws more juice than standard points so it is more suscepticle to low battery and poor charging. With a stock alternator, the engine doesn't spin fast enough at idle to produce enough energy to run motor and brake light let alone headlight. I don't understand why your 3 phase isn't working better, but I would start with a strong battery.This is probably why have to push it to get the alternator spinning fast enough to fire it.

3. I would also check to see if plugs are fouled.

it's only due to sites like these that i'm able to enjoy these vintage machines.

yes, it was from ebay... i'll dig up my link

in the meantime, these are not ideal shots but they were taken from the ebay listing:

Michael is on the money, having had similar troubles it certainly sounds like a new battery would help.
Good luck Mike.