Mercury is Finished for now...

concours

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Back fishtail type wobble completely gone. Did a ride today and handled great in the rear. Back break needs some bedding in I guess but seems better every time I stop.

I know why the front tire front end wobbles and I’m going to make a new post about it because it’s important. So let’s drop that for now.

I built the most uncomfortable bike ever. Foot pegs are ok in position so is seat (seat is damn hard). Handlebars are Low and my back and wrists aren’t loving it. Considering raising the bars above the light for sn extra two inches of lift but might make the bike look stupid.


Newest problem is I was loosing some power in 2/3/4 when gunning it, especially up hill where I got gurgled and some not loud pops. Got to the top of the hill dropped into 1st and turned after stopping. Went up a not steep hill after a stop sign and the bike stalled. Right away I thought spark plugs fouled. Tried to start it but no luck and no tools (rookie mistake). So I put the hazards on and I coasted down the steep hill all the way to my warehouse.

Checked plugs and they’re dry black and sooty powder like charcoal.

So either my ignition timing is off (gotta get a gun I guess) or my carb isn’t correct. Or the air filter was a bad idea.

Suggestions?
Suggestion?
Test, don't guess.
Take the air filter off, ride 5 minutes. Blubbering gone? Then it's too rich, start working back.
Runs the same with air filter on? Keep testing.
Run better when stone cold?
Try it, start up and RIDE OFF, gently, but test it.
 
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Suggestion?
Test, don't guess.
Take the air filter off, ride 5 minutes. Blubbering gone? Then it's too rich, start working back.
Runs the same with air filter on? Keep testing.
Run better when stone cold?
Try it, start up and RIDE OFF, gently, but test it.

Runs better cold it seems, also was running better without air filter. I dropped the pin as suggested above so I’ll try that, if runs worse or spark plugs foul again I’ll take off the air filter and try again. If still bad I’ll report back.

Starts easy and idles well. I don’t have an ear for this stuff so maybe I’m off base saying it idles well.

But yes agree try one thing and think first before trying many things. Hahaha learning to be more patient about life through motorcycles.
 

Fast Eddie

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Starts easily and idles from cold… Runs better when cold… Runs better without the air filter… Dry black plugs…

They are all symptoms of being overly rich.

But as posted by gortniper, you gotta learn to follow the carb tuning advice and sequence given. Different jets and circuits control different throttle openings. But unfortunately there is a large over lap as well, so it is VERY easy to get yourself in a real tiz if you don’t learn this, by getting one part wrong then over adjusting another to compensate, ad infinitum.

A fabulous trick is to mark your twistgrip in quarterly increment, you can then tell at a glance approximately how far open the throttle slide is, and you can then identify which jet / circuit to adjust as a start point.
 
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Starts easily and idles from cold… Runs better when cold… Runs better without the air filter… Dry black plugs…

They are all symptoms of being overly rich.

But as posted by gortniper, you gotta learn to follow the carb tuning advice and sequence given. Different jets and circuits control different throttle openings. But unfortunately there is a large over lap as well, so it is VERY easy to get yourself in a real tiz if you don’t learn this, by getting one part wrong then over adjusting another to compensate, ad infinitum.

A fabulous trick is to mark your twistgrip in quarterly increment, you can then tell at a glance approximately how far open the throttle slide is, and you can then identify which jet / circuit to adjust as a start point.

Yes I agreed with gortnippers suggestion and tested it today as I also msg him about how the bike cuts out up hill when I give throttle. He suggested I move the needle down on rung made sense given the symptoms. This was all it took, the bike runs really well now. I blasted up a tall hill today. Did a long ride no issues with the throttle response and engine. Also bike seemed cooler. Maybe it was a cooler day but overall bike seemed to be running cooler.

I haven’t pulled the plugs yet but I’m hoping they’re in better shape than the plugs were yesterday.

I measured the temperature of the oil in the oil tank right when I turned off the bike and it was reading 150F. Far less smoke coming from the oil tank today. And no engine smoke no exhaust smoke. Auto clutch seems to be ok even though I’m still having problems shifting (same problems I had before I installed the auto clutch).
 
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The rear wobble doesn’t exist anymore. Front there is problems at speed (again I know why and will make a separate post). Nothing that is causing major handling issues so far and I’m getting more confident with my turns etc. I think the bike handles well, wants to stay upright and straight.
 

concours

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The rear wobble doesn’t exist anymore. Front there is problems at speed (again I know why and will make a separate post). Nothing that is causing major handling issues so far and I’m getting more confident with my turns etc. I think the bike handles well, wants to stay upright and straight.
Many times I've seen this be caused by the nut being loose.
 
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Many times I've seen this be caused by the nut being loose.
You mean the steering head nuts? I'm fairly certain it's something else..

Honestly I was going to blast @madass140 (Donald Pender) in another topic because he sent me a warped rim I noticed this but having asked him previously about it on the other wheel he shrugged it off and said it would be fine (ordered three wheels from him total).. The guys at the tire shop also commented that the rim might give me problems because it was warped. Turns out that's likely the issue of the front wobble. When I'm riding it's so warped that I can see the tire moving in and out and I can feel it, at lower speeds it's rhythmic at higher speeds it's a wobble. I'm going to replace the front wheel with a CNW brembo kit and Commando front hub at some point in the future.
I just don't care to anymore to spread the angry msg.. People like his stuff because it's good enough and cheap and looks the biz. Frankly it's why I went with him. And if I didn't have bad luck (QC issues with all his bits) I'd probably be in the pro Donald Pender camp. Turns out I don't have great luck with this stuff so I happened to get some items with minor to large QC issues. Wish he would have done the right thing and just fixed his QC issues but he didn't and that's the risk you take dealing with random people on the internet.

It's not just DP, I've gotten QC issue parts from RGM too, same with a few other suppliers.. Honestly I should have just ordered everything from Andy Molnar or Ken Macintosh the first go and been done with it. Heck I should have picked up one of those CNW Commandos when I had the chance. I didn't, so here I am.

Maybe the wobble wouldn't be so bad if I re-tightened the front end. I'll give it a go.
 
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Bikes running perfectly fine now engine wise. I went for a long drive maybe about 1.5 hours up hills etc no issue no weird noises no weird smoke.
However today when I checked the spark plugs they were also dry black charcoal. So I think I’m still running rich. Should I slightly adjust the air fuel mixture or should I just remove the air filter? Don’t want to do both just want to do one thing. Air filter seems like the easiest and quickest bet but I’m wondering if that’ll be enough. Man need to bring spare spark plugs and a socket with me everywhere I go until this is sorted.
 

concours

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Bikes running perfectly fine now engine wise. I went for a long drive maybe about 1.5 hours up hills etc no issue no weird noises no weird smoke.
However today when I checked the spark plugs they were also dry black charcoal. So I think I’m still running rich. Should I slightly adjust the air fuel mixture or should I just remove the air filter? Don’t want to do both just want to do one thing. Air filter seems like the easiest and quickest bet but I’m wondering if that’ll be enough. Man need to bring spare spark plugs and a socket with me everywhere I go until this is sorted.
Lean it out.
Needle clip.
Even down one size on the main.
Yes, GROSS changes.
Speeds up the process.
I go too far each way, then smaller changes toward target.
Don't worry about the dire warnings about seizures or holing a piston, that happens when the engine is being run VERY HARD, which, from your description, are not.
 
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Read that aside from tuning the carb and setting the ignition timing other causes of black plugs are “excessive driving at low speeds and lots of idling”. This is exactly what I do in the city. Will I be able to work around this somehow?
I’m assuming there was less traffic in the 50s when these engines were designed.
 
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Needle is all the way down on the clip. Will do the air filter thing and check plugs. Failing that I’ll start dealing with mainjets.
 

concours

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Read that aside from tuning the carb and setting the ignition timing other causes of black plugs are “excessive driving at low speeds and lots of idling”. This is exactly what I do in the city. Will I be able to work around this somehow?
I’m assuming there was less traffic in the 50s when these engines were designed.
What fuel are you using?
Unleaded pump gas, we can assume?
 

Fast Eddie

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What type of carb are you using ? Is it a new Premier ? If so, is the choke assembly fitted ?

When you say the needle is all the way down in the clip… that means you've got the clip in the TOP grove right ? You wouldn’t be the first person to get that the wrong way around.
 

concours

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Someone told me to use 98 bc it worked better with the Merc and Commando engines.

Not interested in the octane rating (yet)
Please answer the question regarding UNLEADED, where you get it,
(Here we refer to fuel purchased at gas stations, from a pump, for use in all street vehicles as PUMP GAS, whether it's low grade, or more expensive "premium".
Versus RACE GAS which contains LEAD, long since outlawed for street use.)
Your knowledge of this phenom may be limited. How old are you?
Spark plug coloration is WHY this all matters.
 
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concours

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Read that aside from tuning the carb and setting the ignition timing other causes of black plugs are “excessive driving at low speeds and lots of idling”. This is exactly what I do in the city. Will I be able to work around this somehow?
I’m assuming there was less traffic in the 50s when these engines were designed.
That is old information, and is now null & void if using modern unleaded fuel.

Drive it like you just robbed a bank, instead of like being in a parade.

The reason modern traffic sucks is because we're surrounded by dawdlers, who seem quite content to hold up the lunch line.
 
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What type of carb are you using ? Is it a new Premier ? If so, is the choke assembly fitted ?

When you say the needle is all the way down in the clip… that means you've got the clip in the TOP grove right ? You wouldn’t be the first person to get that the wrong way around.

New Premier yes.
I understand what is happening with my engine and I understand what having a pin buried into the main jet does. So when gortnipper told me to try moving the pin bc the bike has problems after idle I was like oh yeah duh that makes sense. So in short I did not get that wrong but thank you for asking bc I can see how that could slip someone up.

Engine is running great to my untrained ear. No more popping or gurgling or flat spots or deceleration on throttle. Response is good everything seems good. Idle is maybe a bit low at lights or just right bc it isn’t stalling and it’s mostly a one kick start.

Plugs are going charcoal black though. Can write my name with the plugs. I cleaned two sets now bc seems a waste and I am running out to get a few more spark plugs today. Will run the bike tomorrow it’s raining heavy today. But seems I need to solve the black plug problem. Might have to go down a main jet size. But is that like one step down or should I drop like two or five steps.
 
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Not interested in the octane rating (yet)
Please answer the question regarding UNLEADED, where you get it,
(Here we refer to fuel purchased at gas stations, from a pump, for use in all street vehicles as PUMP GAS, whether it's low grade, or more expensive "premium".
Versus RACE GAS which contains LEAD, long since outlawed for street use.)
Your knowledge of this phenom may be limited. How old are you?
Spark plug coloration is WHY this all matters.

Oh sorry the only race gas I have/know of here is methanol and it’s probably expired. I’m buying pump gas 98 unleaded. Bought it from BP in Auckland NZ if any kiwi wants to chime in on the quality of that gas.
 
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