Problems launching my new to me Norton Mercury.

Fast Eddie

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To the uninitiated, simply being ‘on compression‘ can feel like the kickstart has ‘locked up’. So, first question to ask is, are you sure it’s simply not this?

If it really is ‘locking up’ worn cogs in the kickstart mechanism can causes this, basically, instead of the gear teeth meshing, you can get the teeth hitting each other. Putting it into gear and rocking the bike back and forth will move the gears and allow you to try again.

I once had a high compression bike that occasionally did this. One day I mistook the locked up gear for it being on compression, so when I launched all my weight on the kickstart I broke the gear in half !
 

baz

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You all make good points (printing the manuals make a lot of sense). And yeah I thought better of mixing fuel, fire, in my warehouse even though I have sprinkler systems and ventilation and fire extinguishers on hand.

Update:
Basically I took the primary case off and noticed right away the clutch basket was wobbly and when I turned the clutch basket with the clutch pulled in it wobbles. Not sure if this is normal on Norton’s.

Anyway took the clutch plates off and cleaned them in gas, but to be honest they were SUPER CLEAN. Way cleaner than my triumph slickshift gearbox plates. Put it back together and still having problems with the kickstart. I didn’t install the carb or do anything like that. I was just trying to see if it would attempt to kick down easily but it doesn’t.
Yep the clutch will wobble a little when you pull the lever in
I fail to see the danger with a squirt of fuel in a spark plug hole or in the carb to be dangerous!
At least the fuel in both instances is (inside the engine or carburettor) if you tickle the carb the fuel is outside the engine!!!
And you would immediately know if you have a carb problem
 
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It feels like I’m going to break something. At the very least the kick stand lever is not long for this world. I’m trying not to force anything. When I realise it doesn’t want to go I grab the clutch and pump the lever a bunch and try again. Sometimes it works sometimes not. It could be compression as when I take the spark plugs out it kicks down no problems.
 

baz

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It feels like I’m going to break something. At the very least the kick stand lever is not long for this world. I’m trying not to force anything. When I realise it doesn’t want to go I grab the clutch and pump the lever a bunch and try again. Sometimes it works sometimes not. It could be compression as when I take the spark plugs out it kicks down no problems.
Sounds like compression
 
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But then why am I getting such high conpesssion? and side note it’s really tiring and the gas tank is in a terrible place.
Photos are good, and help identify parts that are (non) standard.

I am assuming you get better spark with new plugs (when laid on head) when you kick it?

It woulnt hurt to swap the plug leads to see what happens.

I use HPS 20w50 in my Commando. Not sure what grade is recommended for Mercury. For the Commando in NZ, I wouldnt really run 10w40, especially in town.

The spark was good with the old plugs they were just very black. Spark is good with the new plugs. Tim suggested I check spark distance and adjust accordingly to speck.
He setup the carb for me based on Amal’s advice to him. And I checked his setting with the manuals and websites. So all is good. Just need to install it.

Did the clutch plates today. Feels somehow better than before but something still sees a bit odd with the wobbly clutch basket.
 

baz

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But then why am I getting such high conpesssion? and side note it’s really tiring and the gas tank is in a terrible place.


The spark was good with the old plugs they were just very black. Spark is good with the new plugs. Tim suggested I check spark distance and adjust accordingly to speck.
He setup the carb for me based on Amal’s advice to him. And I checked his setting with the manuals and websites. So all is good. Just need to install it.

Did the clutch plates today. Feels somehow better than before but something still sees a bit odd with the wobbly clutch basket.
"The petrol tank is in a terrible place!!!!" :D :D :D :D :D now that's funny
 

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"The petrol tank is in a terrible place!!!!" :D :D :D :D :D now that's funny
Re the oil tank comment, can I pull my hair out? Kicking it over with clutch lever partially in just creates clutch slip. Please, if bike kicks over with plugs out there is most likely no problem with the kick start mechanism. Instead you simply don't know how to kick over a large capacity bike. This is not like kicking a 125cc dirt bike which you can do just by bending your knee. MAKE CERTAIN BIKE IS IN NEUTRAL in one of the many suggested ways. If the oil tank bothers you, put bike on center stand. Stand on right side of bike with right foot on kickstarter. Find compression - resistance with starter foot rest up as high as it goes. Put weight on starter by smoothly jumping up with bent knee and then straighten knee as your weight comes down on the starter. To get the necessary force you need a combination of weight and straightening. Wear boots so you don't hurt ankle if it kicks back. Some bikes get performance anxiety and don't like people staring when they start. (The last trick is not in the manual.)
 

baz

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Re the oil tank comment, can I pull my hair out? Kicking it over with clutch lever partially in just creates clutch slip. Please, if bike kicks over with plugs out there is most likely no problem with the kick start mechanism. Instead you simply don't know how to kick over a large capacity bike. This is not like kicking a 125cc dirt bike which you can do just by bending your knee. MAKE CERTAIN BIKE IS IN NEUTRAL in one of the many suggested ways. If the oil tank bothers you, put bike on center stand. Stand on right side of bike with right foot on kickstarter. Find compression - resistance with starter foot rest up as high as it goes. Put weight on starter by smoothly jumping up with bent knee and then straighten knee as your weight comes down on the starter. To get the necessary force you need a combination of weight and straightening. Wear boots so you don't hurt ankle if it kicks back. Some bikes get performance anxiety and don't like people staring when they start. (The last trick is not in the manual.)
The more of a crowd the less likely to start that's for sure
 
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I think someone on this forum who is “trusted” by you guys should come over and try and start it since you seem to think it’s me. Believe me when I say that if I want to I can snap the kickstart in half, I’m 98kilos (lost weight due to covid, no gyms, hiding indoors) and I’m relatively young.

In saying that I think you misunderstand the clutch comment. I have to hold the clutch in to work the kick lever to even get it to want to consider coughing/rumbling. Otherwise it’s just so hard to kick that I really would break the lever if I tried.
 
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Re the oil tank comment, can I pull my hair out? Kicking it over with clutch lever partially in just creates clutch slip. Please, if bike kicks over with plugs out there is most likely no problem with the kick start mechanism. Instead you simply don't know how to kick over a large capacity bike. This is not like kicking a 125cc dirt bike which you can do just by bending your knee. MAKE CERTAIN BIKE IS IN NEUTRAL in one of the many suggested ways. If the oil tank bothers you, put bike on center stand. Stand on right side of bike with right foot on kickstarter. Find compression - resistance with starter foot rest up as high as it goes. Put weight on starter by smoothly jumping up with bent knee and then straighten knee as your weight comes down on the starter. To get the necessary force you need a combination of weight and straightening. Wear boots so you don't hurt ankle if it kicks back. Some bikes get performance anxiety and don't like people staring when they start. (The last trick is not in the manual.)
Yes for certain the bike is in neutral if it isn’t when I kick the rear tire will move me forwards.

I’ll try running down the carpark with it in second gear maybe tomorrow when everything is back together. Read that trick in one of those manuals you guys talk so fondly about ;)

Thanks for the Center stand side of bike tip. Seen someone do it on YouTube so I tried it to give the inside of my leg a break. Seriously I need to somehow inset the oil tank a bit. Maybe someone sells smaller ignition coils to make some room to push that oil tank inside the frame a bit.

Speaking of wiring. Yes you are all right that day I took photos of the electronics I hadn’t done any research (as at that point I had no intention of rewiring the bike) but today I’m confident I could rewire the whole bike. I’m NOT going to do it, but I’ve now read two “books” on wiring talked with an electric engineer who’s also a working electrician (he was oddly very helpful for someone who doesn’t own a bike) and have had multiple conversations with they guys ar Alton, Tri-spark, motogadget and have watched a million YouTube videos.

But in saying all that, I’ve done less but still significant amounts of research on why this bike won’t start and nothing seems to make sense. Even if the timing of the electronic sparks were off it would (according to the manual) still run just rough. If the carb was still clogged (not possible) it would still run.
As you guys said, spark, compression, fuel. I can hear the manifold trying to suck in fuel/air when I kick. I can see the sparks. Argh weird.

I mean I’m fairly certain the other day when I was riding it that something wasn’t right with the clutch. I’m hoping it’s not the whole gear box. At this point if it is, I’m probably better off sending it in rather than trying to repair the gearbox myself. But unless the gearbox isn’t spinning the primary chain I don’t think that’s my problem right this second. And with the primary case off I can see the kickstart moving things along.

Maybe the running start will work!
 

baz

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When you had the primary cover off did you notice if the primary chain was slack or tight like a bow string?
 

baz

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Yes for certain the bike is in neutral if it isn’t when I kick the rear tire will move me forwards.

I’ll try running down the carpark with it in second gear maybe tomorrow when everything is back together. Read that trick in one of those manuals you guys talk so fondly about ;)

Thanks for the Center stand side of bike tip. Seen someone do it on YouTube so I tried it to give the inside of my leg a break. Seriously I need to somehow inset the oil tank a bit. Maybe someone sells smaller ignition coils to make some room to push that oil tank inside the frame a bit.

Speaking of wiring. Yes you are all right that day I took photos of the electronics I hadn’t done any research (as at that point I had no intention of rewiring the bike) but today I’m confident I could rewire the whole bike. I’m NOT going to do it, but I’ve now read two “books” on wiring talked with an electric engineer who’s also a working electrician (he was oddly very helpful for someone who doesn’t own a bike) and have had multiple conversations with they guys ar Alton, Tri-spark, motogadget and have watched a million YouTube videos.

But in saying all that, I’ve done less but still significant amounts of research on why this bike won’t start and nothing seems to make sense. Even if the timing of the electronic sparks were off it would (according to the manual) still run just rough. If the carb was still clogged (not possible) it would still run.
As you guys said, spark, compression, fuel. I can hear the manifold trying to suck in fuel/air when I kick. I can see the sparks. Argh weird.

I mean I’m fairly certain the other day when I was riding it that something wasn’t right with the clutch. I’m hoping it’s not the whole gear box. At this point if it is, I’m probably better off sending it in rather than trying to repair the gearbox myself. But unless the gearbox isn’t spinning the primary chain I don’t think that’s my problem right this second. And with the primary case off I can see the kickstart moving things along.

Maybe the running start will work!
Have you kick started a big British twin before?
 
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When you had the primary cover off did you notice if the primary chain was slack or tight like a bow string?
The right amount of slack to a touch tight by eyeballing. I haven’t taken a ruler to it yet (case is still off but it’s 3:30am here will measure tomorrow but seemed maybe a touch tight, need to reference my manuals for the exact travel).
 
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Have you kick started a big British twin before?
Tons of times the first time I started and stalled the bike. It wasn’t doing any of that stuff at first.

Let’s talk about clutch basket wobble. Is it suppose to wobble? Should I take a video of what I mean and post it here (tomorrow). Also if I pull in the clutch and rotate the basket it’s uneven. It was like this before I pulled out the plates and reinstalled them. And I noticed (took note) that it was uneven in the same way it had been when I put back the plates.
 

Fast Eddie

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Let’s talk about clutch basket wobble. Is it suppose to wobble? Should I take a video of what I mean and post it here

Yes !
Some wobble is normal. Too much is not. This kinda subjectiveness is definitely best addressed by posting a video.
But really, you should go to bed…!
 

baz

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Tons of times the first time I started and stalled the bike. It wasn’t doing any of that stuff at first.

Let’s talk about clutch basket wobble. Is it suppose to wobble? Should I take a video of what I mean and post it here (tomorrow). Also if I pull in the clutch and rotate the basket it’s uneven. It was like this before I pulled out the plates and reinstalled them. And I noticed (took note) that it was uneven in the same way it had been when I put back the plates.
Tons of times the first time I started and stalled the bike. It wasn’t doing any of that stuff at first.

Let’s talk about clutch basket wobble. Is it suppose to wobble? Should I take a video of what I mean and post it here (tomorrow). Also if I pull in the clutch and rotate the basket it’s uneven. It was like this before I pulled out the plates and reinstalled them. And I noticed (took note) that it was uneven in the same way it had been when I put back the plates.
I'm not certain on a mercury clutch but most Brit clutches need balancing
IE adjusting each clutch spring to give even lift when you pull the clutch lever
 
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I'm not certain on a mercury clutch but most Brit clutches need balancing
IE adjusting each clutch spring to give even lift when you pull the clutch lever
Good to know. Will definitely do this tomorrow. Will post the wobble video and will adjust the springs a bit to try and get an even amount of pressure. I just put them back the way I found them till I either read more or heard from you guys.

Gonna get new gas tomorrow too.
 
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