Problems launching my new to me Norton Mercury.

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Ok so now I'm feeling like a noob (I am tho) will explain below... Took everyones advice on the other post and decided to just buy a Norton Mercury (I'll make it look cool soon enough) instead of building a bike from scratch. I'll turn my wideline featherbed rolling frame into an EV motorcycle (easy enough to do) and I'll sell off all the random spare/original parts I don't need.

Anyway so here is where I feel stupid. I got a bike off of someone reputable here in NZ who had his mechanic look over it again yesterday before delivering it to me (17k original miles, direct from new import NZ police bike 1970, apparently sat around for ages till 2018 when it was fixed up and kept till it was sold to me now). Primary chain case leaks a bit of oil (I'd probably get a belt drive down the road anyway).

I can get the bike started on first kick, it sounds to my untrained ears like it's stable and I wait a bit for it to heat up. If I move the choke lever on the handlebar I can get it to rev up a bit higher, but if I put it all the way closed it will shut off the bike. Anyway my problem is that when I pop it into 1st gear it stalls out immediately. Sometimes lurching forward sometimes not. I've tried to go straight into second and also the same problem. Am I missing anything? Am I doing something wrong?!

Thanks guys!

ADDING:

Playing with the choke has the bike going in first, I can ride around my carpark. If I slow down in first the engine stalls. If I grab my clutch while stopping sometimes it won’t go when I let go of my clutch. Should I be adjusting the choke till it’s perfect. Or am I just using some type of bad technique?

Also if I just leave it sitting while on it smokes around the front end quite a bit and smells. Typical Norton stuff or do I need to check something?

Also seems my engine is idling at around 2000rpm, shouldn't it be much lower? Is that going to be my issue? Wonder if the choke cable is causing problems?
 

ntst8

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What part of NZ are you in? Sounds like a visit from a local NOCNZ member might be in order.
If it is a standard mercury then single carb?
The choke lever should move approx 1/4 turn between fully on (cable loose) and fully off (cable pulled tight). It is warm here now so if you are using the carb tickler then leave the choke off. If the choke is unecessarily on then the plugs will foul and you will fail to proceed.
Idle - there is a screw to adjust this, worth reading up the Amal guide, available from the Amal website.
 
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Auckland Central.
Standard Mercury, single car going into a double input.
Choke lever moves maybe 260 degrees. I'll check to see if the carb tickler is open.
I can figure out the idle screw but idle RPM is suppose to be 1000?
 

ntst8

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Are there any slides on the end of he choke cables? I ran my Commando for years without so not a panic if there aren't.
I don't know what the books says but 1000 sounds good from here.
If you do want some local input check out the NOCNZ website, Brian Bull is the area rep for Auckland, top bloke and very knowledgeable, his contact details are on the website.
 

gortnipper

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Bad technique. ;)

It sounds like you have two separate issues here:

1. Sounds like you need to adjust the clutch. Not sure how that works on a Mercury.

https://www.nortonownersclub.org/comment/63961#comment-63961 may have some info for you.

You also may want to clean the clutch plates. The Nortons use an oil bath primary, but the plates are actually a dry clutch design that "can" run in oil. But, after so long they might get gummy from the oil. Just bathe them in petrol and wipe them off.

2. per Iain's comment above, learn how to adjust your carb(s):



 

baz

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MOVED TO PROPER PLACE:

Ok so now I'm feeling like a noob (I am tho) will explain below... Took everyones advice on the other post and decided to just buy a Norton Mercury (I'll make it look cool soon enough) instead of building a bike from scratch. I'll turn my wideline featherbed rolling frame into an EV motorcycle (easy enough to do) and I'll sell off all the random spare/original parts I don't need.

Anyway so here is where I feel stupid. I got a bike off of someone reputable here in NZ who had his mechanic look over it again yesterday before delivering it to me (17k original miles, direct from new import NZ police bike 1970, apparently sat around for ages till 2018 when it was fixed up and kept till it was sold to me now). Primary chain case leaks a bit of oil (I'd probably get a belt drive down the road anyway).

I can get the bike started on first kick, it sounds to my untrained ears like it's stable and I wait a bit for it to heat up. If I move the choke lever on the handlebar I can get it to rev up a bit higher, but if I put it all the way closed it will shut off the bike. Anyway my problem is that when I pop it into 1st gear it stalls out immediately. Sometimes lurching forward sometimes not. I've tried to go straight into second and also the same problem. Am I missing anything? Am I doing something wrong?!

Thanks guys!

ADDING:

Playing with the choke has the bike going in first, I can ride around my carpark. If I slow down in first the engine stalls. If I grab my clutch while stopping sometimes it won’t go when I let go of my clutch. Should I be adjusting the choke till it’s perfect. Or am I just using some type of bad technique?

Also if I just leave it sitting while on it smokes around the front end quite a bit and smells. Typical Norton stuff or do I need to check something?

Also seems my engine is idling at around 2000rpm, shouldn't it be much lower? Is that going to be my issue? Wonder if the choke cable is causing problems?
Choke off position is the lever fully open IE cable tight
All the way clockwise
Many people get this wrong when they first own a British bike
You definitely want the choke off when the engine is warm
 
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Are there any slides on the end of he choke cables? I ran my Commando for years without so not a panic if there aren't.
I don't know what the books says but 1000 sounds good from here.
If you do want some local input check out the NOCNZ website, Brian Bull is the area rep for Auckland, top bloke and very knowledgeable, his contact details are on the website.
Check out the photos I just posted above.
 
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Bad technique. ;)

It sounds like you have two separate issues here:

1. Sounds like you need to adjust the clutch. Not sure how that works on a Mercury.

https://www.nortonownersclub.org/comment/63961#comment-63961 may have some info for you.

You also may want to clean the clutch plates. The Nortons use an oil bath primary, but the plates are actually a dry clutch design that "can" run in oil. But, after so long they might get gummy from the oil. Just bathe them in petrol and wipe them off.

2. per Iain's comment above, learn how to adjust your carb(s):



Thanks, going to look over these now. Clutch plates shouldn't be to problematic to clean I've already dismantled and put the slick shift back together I'm assuming this is very similar. Might just get a new clutch cable, I think new cables all around is sensible. I actually don't want a choke on the handlebars so I'm going to pull off the carb at some point and peak under the shrink wrap.
 

baz

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Your first photo is choke off
Is that how you are using it?
 

ntst8

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And the choke lever movement looks more like 135 degrees rather than 260, which looks reasonable. My 1/4 turn was a bit mean now that i have gone out and had a look.
 
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Your first photo is choke off
Is that how you are using it?
Yes that causes the engine to rev about 2000rpm. In the second photo the choke would cause the engine to stall out at around 800 or less (sometimes), sometimes it doesn't do anything which I think is just a sticky cable?
 
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And the choke lever movement looks more like 135 degrees rather than 260, which looks reasonable. My 1/4 turn was a bit mean now that i have gone out and had a look.
Sorry don't know why I said 260 meant 180 but yeah looks like less than 180.
 

Fast Eddie

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That’s an old, original, Amal concentric that’s been stood for ages.

Therefore it’s almost certain that the pilot jet (a none removable pressed in bushing) is fully or partially blocked. And if it is, you’ll be fruitlessly chasing your tail until it’s dealt with.
 
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That’s an old, original, Amal concentric that’s been stood for ages.

Therefore it’s almost certain that the pilot jet (a none removable pressed in bushing) is fully or partially blocked. And if it is, you’ll be fruitlessly chasing your tail until it’s dealt with.
Details of pilot circuit, you will need a #78 or a 16 thou drill bit.


and at some point you need to change out that plastic banjo on the bottom of the float chamber for a metal one, not urgent but add it to the 'To do list''.
 
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That’s an old, original, Amal concentric that’s been stood for ages.

Therefore it’s almost certain that the pilot jet (a none removable pressed in bushing) is fully or partially blocked. And if it is, you’ll be fruitlessly chasing your tail until it’s dealt with.
Should I take it apart and clean it or should I replace the whole carb?
EDIT: Will try the Bushman's method of cleaning it first!
 
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Ok so far list of things to do:

1) Clean the clutch plates
2) Remove and clean the carb
3) Replace the clutch/choke/brake cables

Start the bike up and play with the pilot screw to see if I can get the idle RPM to 1000 and have it not stall when just idling. Will report back on this!


Any thoughts on the smoking? Don't see any oil leaks on the heads or barrels or crank case, maybe a drip or two from the crank case (maybe) but I'm fairly certain the only oil drips are from the primary case. Why would it smoke?
 
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Ok so far list of things to do:

1) Clean the clutch plates
2) Remove and clean the carb
3) Replace the clutch/choke/brake cables

Start the bike up and play with the pilot screw to see if I can get the idle RPM to 1000 and have it not stall when just idling. Will report back on this!


Any thoughts on the smoking? Don't see any oil leaks on the heads or barrels or crank case, maybe a drip or two from the crank case (maybe) but I'm fairly certain the only oil drips are from the primary case. Why would it smoke?
Could be gummed up rings from standing so long, riding it should cure that, or could be a number of other issues that could or could not be cured by using the bike. You will just have to ride it and see if it clears up, if not then note when it smokes most, on the over run ie a closed throttle or when accelerating hard. That will give a clue where to look as would a leak down test.
 

baz

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Ok so far list of things to do:

1) Clean the clutch plates
2) Remove and clean the carb
3) Replace the clutch/choke/brake cables

Start the bike up and play with the pilot screw to see if I can get the idle RPM to 1000 and have it not stall when just idling. Will report back on this!


Any thoughts on the smoking? Don't see any oil leaks on the heads or barrels or crank case, maybe a drip or two from the crank case (maybe) but I'm fairly certain the only oil drips are from the primary case. Why would it smoke?
How long has it stood? Did you drain the sump at all? Could just be wet sumped
Don't put any oil in the tank until it has run for a while
If you already have then check the oil level in the tank
 
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How long has it stood? Did you drain the sump at all? Could just be wet sumped
Don't put any oil in the tank until it has run for a while
If you already have then check the oil level in the tank
I don't know what the bike seller and his mechanic did oil etc wise. It say from 1973-2018 where it was cleaned up/gone over by a mechanic and then kept till yesterday where it was outfitted with a new battery and given a ride around.

I have not done anything yet other than fire it up and ride it in circles around my carpark. I let it idle for a bit while playing around with the choke and it was pretty constantly stuck at 2000 rpm while in neutral. Gave it some throttle once in a while and within maybe two minutes of idling it started to smoke near the front of the bike around the cylinder head I guess. So I turned it off.
 
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