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I need some collective problem-solving. I was planning to take McKnight in for inspection today, but I don't like how the bike's running. First, it's running lean - I can get it to about 3800 rpm, but under load, it's not going above that. WOT leaves me right there, too. I've checked vent hoses, ducts, fuel lines - all look ok. So I'm thinking that I might have a problem with one (or both) of the needles/jets, but before I go yanking the carbs off again, anybody have thoughts? It runs pretty well at 1/4 throttle and speeds around 30mph. But that's all it's got. It'll never even get into town at that rate.

It's also running warm. I had some trouble with the fan (basically, it's broken), so I cannibalized the fan off of Orleans; and when I changed the fan, I drained the radiator and refilled with the bleeder valve open, so if there was an air bubble, there shouldn't be now. I also put in a little more oil because the oil level was below the sight glass line. But it's still running too warm. If I'm running lean, that can cause the bike to run hot, right, until basically it melts itself into one big hunk of unattractive and un-fixable aluminum?

What am I missing?? :confused:
 

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Possible vacuum leak. Try spraying WD40 around the carbs and boots [email protected] a low idle. If you have a vacuum leak the idle should increase. Yes you are correct about running lean makes more heat.
 

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Discussion Starter #3
Possible vacuum leak. Try spraying WD40 around the carbs and boots [email protected] a low idle. If you have a vacuum leak the idle should increase. Yes you are correct about running lean makes more heat.
'Cause it's sucking up the WD40 and doing something untoward in there? I'll give it a few sploots and see what happens. If I don't have to pull the carbs, I'll be delighted...but one does what one must.

Another question: if I have a vacuum leak, would that cause my idle to just be "off"? At first I thought I had a stuck float bowl, 'cause the bike was idling high (hardly touched the throttle). But if I played with the idle adjust knob to reduce the rpms, the bike would die. I think it was a little better today (in terms of not staying at high idle), but I definitely am having trouble getting that to settle out.

Hey, Hyper! Idea for my new avatar - could really use a sledgehammer in there about now! :D
 

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Cindy I'm betting on a vacuum leak of some sort. The high idle is a pretty sure sign of that. You can also use B12 carb cleaner to shoot around the carbs and intakes, carb mounts and such to find vacuum leaks. What I've found with either WD40 or B12 is that the engine bogs down when you hit a leak. Your mileage may vary.
 

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Discussion Starter #5
Thanks, Fergy - turns out that as I was searching for a vacuum leak (spraying WD40 up around the carb boots on the air intake box), I noticed a lovely set of sparks coming off the rear ignition coil. "Hmmm," I said to myself. "I do believe those fireworks should not be there." Pulled the coil, and there were some crimps inthe wires - the coil was grounding itself against the exhaust chamber. Taped up all the visibly open points, reinstalled the coil, and took the bike back out last night - ran like a charm. Didn't heat up beyond the leftmost side of the symbol on the thermo gauge, punched it to 6K rpm in 4th gear, 65 mph, and not a problem. So I guess I was running on fewer than 4 cyls (I've been told that before, but, ya know...). I pm'd Dennis that the engine block itself felt really warm to me when I got back to the house (just a lot of heat coming up off the block), but a) it was 85 degrees and humid out at 8.15pm, b) I haven't ridden in the heat in awhile, and c) there was no indication otherwise that my bike was overheating. So I'm assuming it's fine.

Sooooo, we'll try this little trip for inspection again tonight... :beerchug:
 

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Discussion Starter #7
Fireworks you say? Wow! It's always nice to find the problem. Glad you didn't spray the sparks! :wow:
Yeah...that'd be something that even safety goggles wouldn't protect against! Guess WD40 has a higher flash point than other combustible fluids 'cause I was mighty, mighty close...
 

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I think Crobins365 should forever be known as Sparky365
 

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Yo, Sparky, did ya pass ?
 

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Cindy -

I was going to suggest you check to make sure it's running on both cylinders as mine acted the same way when I forgot to connect the rear coil.

Let us know.

Carb cleaner is a great leak detector, rpm's go up if it ingests any.

Jon
 

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Discussion Starter #11
Yo, Sparky, did ya pass ?
LMAO - got McKnight into town tonight without a problem. Had all my gears, hit 80 mph briefly (YIKES! Jon, you do that regularly?!?!?!), rpms were kicking up nicely, all the important things (headlamp, turn signals, horn) worked fine, AND, best of all, nothing caught on fire. So here's hoping!! :beerchug:
 

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Cindy -

I do what regularly?? If you referring to hitting 80 mph, yes, one of the driving factors to getting the Meanstreak. It only pulls 3750 rpm at 80 mph. The 750 was close to 6K at that speed.

So, your problem is solved and it was the coil? Whole lot easier than pulling the carbs again.

I am getting ready to pull the motor on the 750 (yeah, I know I said that before) so I will be needing the puller. Any details about the "penny" I should know?
Did not see any pics from you on that.

Just cause I bought a Meanie doesn't mean (no pun intended) that I am not checking this place out all the time.

Jon
 

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Discussion Starter #13
Cindy -

I do what regularly?? If you referring to hitting 80 mph, yes, one of the driving factors to getting the Meanstreak. It only pulls 3750 rpm at 80 mph. The 750 was close to 6K at that speed.

So, your problem is solved and it was the coil? Whole lot easier than pulling the carbs again.

I am getting ready to pull the motor on the 750 (yeah, I know I said that before) so I will be needing the puller. Any details about the "penny" I should know?
Did not see any pics from you on that.

Just cause I bought a Meanie doesn't mean (no pun intended) that I am not checking this place out all the time.

Jon
Yeah, 80mph with no airbags - zoinks! I must be getting old...:zzz:

It definitely was the coil, and I'm just glad that the engine didn't have to go up in a puff of Vulcan smoke for me to figure that out. And, yes, anything not to have to pull the carbs again - anything!!

I got held up on Orleans' engine while i was fixing McKnight - at present, I have no gears on it to demonstrate the penny technique. But I can photograph the penny itself and you can see why the recommendation is for copper... I'll try to get the cam balancer back on tomorrow, and can take pics once all that stuff's in place.
 

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Yeah, 80mph with no airbags - zoinks! I must be getting old...:zzz:

It definitely was the coil, and I'm just glad that the engine didn't have to go up in a puff of Vulcan smoke for me to figure that out. And, yes, anything not to have to pull the carbs again - anything!!

I got held up on Orleans' engine while i was fixing McKnight - at present, I have no gears on it to demonstrate the penny technique. But I can photograph the penny itself and you can see why the recommendation is for copper... I'll try to get the cam balancer back on tomorrow, and can take pics once all that stuff's in place.
Cindy -

Thanks, appreciate it!

You're still a good few birthday's behind me.

Jon
 

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Cindy, so glad you fixed it! Now you can be riding when you aren't in the mood for fixin'. :smiley_th And speaking of age, I'm probably ahead of most in the birthday category, along with the cheeseburgers too!:(
 

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:smiley_th And speaking of age, I'm probably ahead of most in the birthday category:(
Maybe we should start an over 50 club.....

Never mind, that could be most of us.
 

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Maybe we should start an over 50 club.....

Never mind, that could be most of us.
Okay, so there's at least two of us as members!

Jon
 

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Cindy, glad you figured your problem out. RIDE SAFE.
 
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