Norton Dominator 99 problems

Re: Norton Dominator 99 problem?

texasSlick said:
The Atlas directs the oil mist to the chain guard in an attempt to oil the chain ..... an utterly worthless endeavor, IMO. The chain speed is too fast to capture the oil, and the oil is slung forward and deposited on the drive side crank case. I suspect the chain actually creates a wind under the guard that captures the breather gasses even before the gasses contact the chain. I fitted a guard to the inside of the inner primary cover to capture the slung oil and allow it to drip to ground. Oil also deposits on the rear wheel.

My solution to oil mist was to fabricate a scrubber cartridge that is inserted into the tower of the oil tank. Refer to atlas-dommie-oil-mist-scrubber-t19002.html?hilit=Atlas/Dommie%20oil%20scrubber#p240772

Slick

Since you did this mod over 3 years ago, what is the latest update in use :?:
Norton’s oil tank tower was a 1960s attempt to solve the oil mist problem which IMO was slightly better than the earlier version
 
Re: Norton Dominator 99 problem?

Hello,

My engine breather hose is shortened and fitter breather filter to it, i understood that it should not be so messy anymore.

I dont think that i am so happy with the oil flow to rockers so im going to improve that next, we'll see how it'll do.

Has anyone improved oil flow to rockers in these return line rocker feed systems?

-Kuusisto
 
Re: Norton Dominator 99 problem?

What you appear to have is standard oil lines for pre-commandos.
I suspect that you may be confusing the low pressure feed to the rockers with the breather
Normally the return line from the oil junction (lower RH rear crankcase) to the oil tank has a tee to the rocker feed (there are exceptions to this where the rocker feed is from the lower (HP) feed from the timing cover (e.g.: some 650SS)
The breather from the LH rear of the crankcase (just below barrel) is also normal (Except Atlas which breathes out through LH end of cam tunnel). This hose is normally connected to the "froth" tower on the oil tank
From your photos I can't see anything that is not as Norton originally intended it to be
Cheers
Rob
 
Re: Norton Dominator 99 problem?

Hello,

I was checking oil feed and came up with this poorly soldred pipe.


Norton Dominator 99 problems

Left hand rocker feed banjo snapped off. Guess its time to go local hydraulic shop ask if they could make new lines.
 
Re: Norton Dominator 99 problem?

robs ss said:
What you appear to have is standard oil lines for pre-commandos.
I suspect that you may be confusing the low pressure feed to the rockers with the breather
Normally the return line from the oil junction (lower RH rear crankcase) to the oil tank has a tee to the rocker feed (there are exceptions to this where the rocker feed is from the lower (HP) feed from the timing cover (e.g.: some 650SS)
The breather from the LH rear of the crankcase (just below barrel) is also normal (Except Atlas which breathes out through LH end of cam tunnel). This hose is normally connected to the "froth" tower on the oil tank
From your photos I can't see anything that is not as Norton originally intended it to be
Cheers
Rob

Hello, i believe that my oil tank is not original one since it doesnt have anything where i could connect breather hose.

I heres picture:

Norton Dominator 99 problems

Red stripe - oil feed to pump

Blue stripe - Oil return to tank

PurpIe ring - Rocker feed banjo

Purple stripe - Rocker feed pipe

Green stripe - Engine breather hose, which is no longer connected.

Normal pic:

Norton Dominator 99 problems

Heres pic of the T-coupling where breather used to be connected:

Norton Dominator 99 problems
 
Re: Norton Dominator 99 problem?

Well, desided to try to solder the pipe myself and it came out fine, no leaks and strong joint.

The hole in the fitting was 5,2-5,3mm i think and i tapped it with M6. Secured 6mm bolt with loctite, cutted the bolt and turned flat with the fitting(on lathe). Drilled 3mm hole through, assembled it and tried out, it was spot on.

So the restriction is now about 2,2-2,3mm due to original hole, when whatching inside cylinder head without rocker caps on, you can see small amount of oil coming out between rocker shaft and rocker itself. Its not pouring but you can see oil gathering there and coming down the wall slowly, I think thats enough for me, i was not able to see that earlier without modification, also oil came back to the tank with good flow.
Now i am completely sure rockers will get plenty of lubrication and ride it in peace.

And by the way, no smoking was spotted during about 1hour run with hot engine and oil. I will keep an eye out for smoking if it will happen.

-Kuusisto
 
Re: Norton Dominator 99 problem?

Re;” The Atlas directs the oil mist to the chain guard in an attempt to oil the chain ..... an utterly worthless endeavor, IMO. The chain speed is too fast to capture the oil, and the oil is slung forward and deposited on the drive side crank case"

An alternative to that is to obtain the bottom part of a Scotoiler that bolts onto the rear spindle and put your oil breather into this and oil near the rear sprocket.
 
Re: Norton Dominator 99 problem?

Hello,

The breather hose is not attached to anywhere at the moment(hose is directed to ground) but i dont know if im leaving it that way since i dont feel good if some oil might come out there with mist.

Maybe ill direct it to rear chain, but since its almost useless to lubricate it(?) and/or making swingarm and rear tire messy, maybe i would bring it up next to carburetor and fit breather filter to it.

Norton Dominator 99 problems
^this is the filter i am talking about.

I have understood that filter should eliminate oil mist coming out almost completely, and its washable and resuable, but dunno the truth. But bringing it up higher than breather outlet is, it should not push oil out that easy? Compared to directing it straight down.

What would be the best place to direct/attach it in your opinion? Attaching it to oil tank is not possible without modifications to the tank.

I removed oil lines today and going tomorrow to the hydraulic shop and get new ones, maybe braided lines dont know yet, well see.

Norton Dominator 99 problems
Old lines..

Regards,

-Kuusisto
 
Re: Norton Dominator 99 problem?

Heh,

I cannot understand these imperial threads..

I tried to measure them with caliper, but i've never got any logical answers/readings.

For example what size is this? The pic is bad quality sorry for that

Norton Dominator 99 problems

Is it like 1/4"? Since upper scale has 16 marks and 16th is 1inch, zero is located at 4th mark.

Still, it doesnt seem to be 1/4" thread, maybe more like 1/8"?

I would like to know what sizes are rocker feed banjo bolts, but i cannot figure it out. Im just wondering if they will have that kind of banjo bolts at the hydraulics shop i'll go tomorrow. And by the way are the banjo sizes universal ?

It would be good and helpfull to learn to read imperial scales and recognize differend thread sizes. When i always have needed something imperial i've always needed to go get it with the worn part with me..

-Kuusisto
 
Re: Norton Dominator 99 problem?

Some previous owner has done something very strange to your return line from the engine to the oil tank. Your "green" line diverts pressurized oil returning to the tank before it gets to your "purple" line which should be the feed from the return to the head/rockers. This makes no sense since set up this way the "green" line would have a more or less constant flow of pressurized oil (ok it would be somewhat sporadic since the return side of the pump outpaces the feed). The flow in the "green" line would be totally unrelated to crankcase pressure so would not serve as a breather. Also unless the "green" line returns to the oil tank it seems to me it will eventually dump out enough oil to empty the system. Not familiar with 99 engines, but suspect that, like the 650, they have a timed breather at the primary side of the camshaft leading to an outlet with a hose fitting in the back topside of the crankcase on the primary side.
 
Re: Norton Dominator 99 problem?

You will find British thread info here
technical-information-t2357.html

The banjo bolts are 1/4-20 x 1 inch BSC. I think (think means I am not certain) all British banjos are universal size.

I agree with Bodger regarding your green line, but as I understand from your post, this line is no longer connected to anything .... that is well and good.

The rocker feed line should come off a banjo fitting at the oil return line (the inboard one), just before it enters the oil tank (about where you have the purple circles). A pic would help, but I am not where I can give you one just now.

Slick
 
Re: Norton Dominator 99 problem?

Hello,

Its good to hear that you think the breather hose should never been there.

Maybe as kernel65 said earlier it might had something to do with wetsumping, i dont know if the engine has wetsumped and you start it, could it push "lots of" oil out of the breather? If this was the previous owners "problem" and then he tought he'll attach it to the return line without thinking about it all the way.

Thank you Slick for the technical data about threads, i will have a look.

-Kuusisto
 
Re: Norton Dominator 99 problem?

Hello,

Everything did not go as i would probably wanted to, but atleast all hoses are new.

The hydraulic shop was not familiar with the banjos and their bolts so i needed to reuse them and use hose clamps but thats fine. Since there was no new banjos i did not take braided hoses. Totally all the parts cost 28,90€ (about 26£)

Heres few pics.

Norton Dominator 99 problems
All parts

Norton Dominator 99 problems
Old banjos cleaned and re-used

Norton Dominator 99 problems
Also oil pressure gauge got new hose replacing that 3mm pipe(i had to use little bit pipe at both ends and connected hose between copper pipes with clamps)

Norton Dominator 99 problems
Rocker feed

Norton Dominator 99 problems
T-branch for rockers

Norton Dominator 99 problems
Also new hoses between oil tank and junction block pipes. Hoses are with pressed fitting oil tank side.

Thats pretty much all for the oil lines, heres also one pic of breather hose.

Norton Dominator 99 problems
Breather hose is the one with the blue breather filter attached to it, and its brought little bit higher than breather outlet is. I will keep eye on it if will leak oil or make some kind of mess.

-Kuusisto
 
Re: Norton Dominator 99 questions

Hello,

Can i just ask my stupid questions to this same thread, since i would not like to make always new one with differend subjects.(edited this thread subject).

I went for a ride today, it worked fairly well, but somehow it feels like losing power at higher revs, its like pulling good until certain point and then it doesnt feel powerful only revs get higher.(clutch is not slipping)

I thought that it might be my mufflers? I've heard that restricting mufflers could restrict power at higher revs? They are original pear drop silencers but they are emptied and replaced with short tube thats blocked completely other end and has small holes to the side of the tube, i would think that would restrict pretty much exhaust gas flows, atleast at higher rpm.

And the breather did work pretty well, it was not messing anything.

How common method is to run the bike without battery? My bike doesnt have battery, i am not sure if it has alternator or dynamo(if this has been used on Nortons?) Only two wires come out of the alternator/dynamo. I noticed that my primary oil had leaked and it was running low on lubrication, so the cover was little bit hotter than normal i think..

I noticed this since i started to marvel the dim headlight bulb at idle and revs, so did my charger(alternator/dynamo) brake due overheating or could this just been temporary since it was hotter than normal, also primary chain was pretty hot.(lack of lubrication) I have ammeter attached to the bike and it has been reading 4amps at idle and normally riding at highway speeds +8amps. When it was hot i was reving the bike at neutral and ammeter did not go to 8amps anymore but was still 4amps at idle, i will start it tomorrow when its cold and check if lights are still dim. By the way its 12volt system.

Norton Dominator 99 problems
This is the only pic i have from primary. It seems to be Lucas system but hard to see the stampings, i will check it when i open primary cover.

I will need to try to seal the primary cover oil tight, once i have removed cover i will check everything is ok inside. I'll try to get it oil tight with rtv silicon

I've seen that there is belt conversions available also to Dominators, any pros and cons? I've read that it might be little difficult to get all the parts fit
But with belt drive you could run it dry.

If i would attach belt drive to my bike, should i have rear hub replaced to commando since it has shock rubbers mounted rear hub and dominator has them inside the clutch. Or is it possible/comfortable to ride the bike without shock rubbers? Or will the belt function kind of shock absorder?

Sorry for all these questions again, and thank you in advance.

-Kuusisto
 
Re: Norton Dominator 99 questions

KuusistoNorton said:
Hello,

Can i just ask my stupid questions to this same thread, since i would not like to make always new one with differend subjects.(edited this thread subject).

I went for a ride today, it worked fairly well, but somehow it feels like losing power at higher revs, its like pulling good until certain point and then it doesnt feel powerful only revs get higher.(clutch is not slipping)

I thought that it might be my mufflers? I've heard that restricting mufflers could restrict power at higher revs? They are original pear drop silencers but they are emptied and replaced with short tube thats blocked completely other end and has small holes to the side of the tube, i would think that would restrict pretty much exhaust gas flows, atleast at higher rpm. Main jets too small can also cause poor power above 4000 rpm. Norton Manual specifies [HASHTAG]#270[/HASHTAG] main jet for 650.

And the breather did work pretty well, it was not messing anything.

How common method is to run the bike without battery? My bike doesnt have battery, i am not sure if it has alternator or dynamo(if this has been used on Nortons?) Only two wires come out of the alternator/dynamo. I noticed that my primary oil had leaked and it was running low on lubrication, so the cover was little bit hotter than normal i think.. You can run without battery if you have a magneto. However, if you have an electronic voltage regulator fitted, it is better to have a small battery ... I have a 2.9 amp-hour battery and Podtronics regulator on my Atlas.

I noticed this since i started to marvel the dim headlight bulb at idle and revs, so did my charger(alternator/dynamo) brake due overheating or could this just been temporary since it was hotter than normal, also primary chain was pretty hot.(lack of lubrication) I have ammeter attached to the bike and it has been reading 4amps at idle and normally riding at highway speeds +8amps. When it was hot i was reving the bike at neutral and ammeter did not go to 8amps anymore but was still 4amps at idle, i will start it tomorrow when its cold and check if lights are still dim. By the way its 12volt system. 4 amps with lights on is normal.

This is the only pic i have from primary. It seems to be Lucas system but hard to see the stampings, i will check it when i open primary cover.

I will need to try to seal the primary cover oil tight, once i have removed cover i will check everything is ok inside. I'll try to get it oil tight with rtv silicon Bond the large rubber to the inner primary cover flange. Next, apply a generous bead of silicone to the 3/8" (9mm) edge of rubber seal, and to the mating shoulder of the outer primary cover. The object is to have the two beads merge after fitting the cover. Allow 24 hours cure time before adding oil. I use Ford type F auto transmission fluid rather than oil .... ATF has better friction coefficient than oil, and does not deteriorate the rubber shock cushions as oil does.

I've seen that there is belt conversions available also to Dominators, any pros and cons? I've read that it might be little difficult to get all the parts fit
But with belt drive you could run it dry. I will let others give their opinions on this issue.

If i would attach belt drive to my bike, should i have rear hub replaced to commando since it has shock rubbers mounted rear hub and dominator has them inside the clutch. Or is it possible/comfortable to ride the bike without shock rubbers? Or will the belt function kind of shock absorder? I operated my Atlas for about 15K miles with a Commando clutch having no shock rubbers. I had no problems, but OTH, I was not racing about as I formally done when I was younger. I became concerned (rightly or wrongly) that even gentle riding might cause gearbox problems, and I returned to the pre-Commando clutch with shock rubbers. The belt gives some cushion to the drive line, but not as much as some may think

Sorry for all these questions again, and thank you in advance.

-Kuusisto

Slick
 
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Re: Norton Dominator 99 questions

KuusistoNorton said:
My bike doesnt have battery, i am not sure if it has alternator or dynamo

It's an alternator, a later encapsulated stator type, possibly RM21.
 
Re: Norton Dominator 99 problem?

Thank you for answering!

Slick, i have single carb fitted to my bike and its an Amal 930 R300. I could remember it was fitted with #320 main and #90 jet needle?(the one that has two small holes in the hex) + velocity stack, dont know which slot needle is atm. Its running good tought, doesnt have any typical symptoms of rich running, plugs seem to be fine imo, atleast not running lean.
Norton Dominator 99 problems
Heres pic, green one i consider as main jet and it was #320 and red one i consider as pilot jet/needle jet and was #90.

I can start the bike usually with 1-2kicks, no more than 3ever, one thing is interesting that you dont have to choke it when you're starting it, never need to use choke, could it perhaps be running little too rich then?

I am using same 20w50 mineral engine oil in primary chain case that i am using in my engine. First time i tried ATF and it worked fine first day and and my second ride of the week my clutch started slipping so i changed oil and cleaned clutch and it was not slipping anymore.

I will need to take mufflers off and see if i could come up with better solution than the current one is. I could recon that previous owner emptied mufflers (kind of straight pipe) and maybe it was too loud and then he made the mods. I would say its 1" 3/4 to 2" pipe which is about 9" long and other end is completely blocked and has small holes at side. So the exhaust gasses hit the blocked "wall" and are forced to go through these small holes, i think its very restrictive.

It sounds nice at idle, but also loses its tone at higher revs. If i would have time tomorrow i would change mufflers from my Moto Guzzi and try them out, they are free flow type of mufflers.

-Kuusisto
 
Re: Norton Dominator 99 problem?

KuusistoNorton said:
Thank you for answering!

Slick, i have single carb fitted to my bike and its an Amal 930 R300. I could remember it was fitted with #320 main and #90 jet needle?
Here http://amalcarb.co.uk/carburettor-for-a ... 67-68.html they state a 220er mainjet for a Domi-99.

(the one that has two small holes in the hex) + velocity stack, dont know which slot needle is atm. Its running good tought, doesnt have any typical symptoms of rich running, plugs seem to be fine imo, atleast not running lean.

Norton Dominator 99 problems
Heres pic, green one i consider as main jet and it was #320 and red one i consider as pilot jet/needle jet and was #90.
Both are Jetholders. Also have a look here: http://www.jba.bc.ca/Bushmans%20Carb%20Tuning.html
This is a velocity stack http://amalcarb.co.uk/media/catalog/pro ... iginal.jpg

I can start the bike usually with 1-2kicks, no more than 3ever, one thing is interesting that you dont have to choke it when you're starting it, never need to use choke, could it perhaps be running little too rich then?

I am using same 20w50 mineral engine oil in primary chain case that i am using in my engine. First time i tried ATF and it worked fine first day and and my second ride of the week my clutch started slipping so i changed oil and cleaned clutch and it was not slipping anymore.

I will need to take mufflers off and see if i could come up with better solution than the current one is. I could recon that previous owner emptied mufflers (kind of straight pipe) and maybe it was too loud and then he made the mods. I would say its 1" 3/4 to 2" pipe which is about 9" long and other end is completely blocked and has small holes at side. So the exhaust gasses hit the blocked "wall" and are forced to go through these small holes, i think its very restrictive.

It sounds nice at idle, but also loses its tone at higher revs. If i would have time tomorrow i would change mufflers from my Moto Guzzi and try them out, they are free flow type of mufflers.
https://www.feked.com/norton-exhaust-silencer-dominator-650ss-atlas-650-750cc-1962-on.html. Those looks great but the sound? Idont know

-Kuusisto

Fritz
 
Re: Norton Dominator 99 questions

KuusistoNorton said:
How common method is to run the bike without battery? My bike doesnt have battery, i am not sure if it has alternator or dynamo(if this has been used on Nortons?) Only two wires come out of the alternator/dynamo.

-Kuusisto

Your MUST have some method of limiting the alternator voltage to run without a battery. Either a Zener diode or an electronic regulator (preferred), otherwise the voltage can become so high it will burn out every light bulb in the system. Since you have not reported any problems of this sort, I presume the PO has fitted a regulator.

The battery acts as a capacitor and smoothes the voltage waveform. This makes the regulator more efficient. As I noted in previous post, with a magneto ignition, even a small amp hour battery will suffice.

Slick
 
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