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Old 06-05-2013, 02:23 PM   #46
LarryDawg
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not yet

I tore the TL down last nite so I can do some mild mods and repaint it, replace a couple of seals, thinking about putting a headlight and tail light on it and getting it street legal (I did leave the lighting coils in it when I built it!!!!) it is still really tight and just going to freshin up a bit and repaint it.
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Old 06-05-2013, 03:01 PM   #47
UtahGuido
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Quote:
Originally Posted by Twin-shocker View Post
From the look of your plug, it seems to me your fuel level is overly high, and as long as tappet clearances are correct, and ignition system is working properly, I would suggest removing carb and carefully checking for perforated float (very common on these bikes). New floats are available, and will resolve issues with high fuel level, if the original was damaged.
And thank you. I was wondering about the float. I really haven't done a thing to this engine, not even a checked the valves.
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Old 06-06-2013, 12:20 AM   #48
Twin-shocker
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Originally Posted by UtahGuido View Post
And thank you. I was wondering about the float. I really haven't done a thing to this engine, not even a checked the valves.
If your TLR was standing for any length of time before you got it, then perforated float is very likely. What tends to happen is only one side perforates, which tends to make the fuel level higher, and makes bikes run very rich.

Take the carb off, taking care not to invert it so fuel flows out, then remove float bowl, and take off the floats. If the floats are leaking you will be able to hear the fuel inside when you shake the floats.

Also well worth checking tappet clearances (2 thou inlet and exhaust), cleaning out centrifugal crank sludge trap, gauze oil strainer (behind drain plug), and refilling with fresh oil.
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Old 06-06-2013, 09:50 AM   #49
UtahGuido
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Quote:
Originally Posted by Twin-shocker View Post
If your TLR was standing for any length of time before you got it, then perforated float is very likely. What tends to happen is only one side perforates, which tends to make the fuel level higher, and makes bikes run very rich.

Take the carb off, taking care not to invert it so fuel flows out, then remove float bowl, and take off the floats. If the floats are leaking you will be able to hear the fuel inside when you shake the floats.

Also well worth checking tappet clearances (2 thou inlet and exhaust), cleaning out centrifugal crank sludge trap, gauze oil strainer (behind drain plug), and refilling with fresh oil.
A float that doesn't float wouldn't be worth much, eh?

Yeah, I've got to set aside some time to lay hands on this motor. The fact that it runs and is quite rideable has forestalled the urgency.
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Old 06-06-2013, 03:35 PM   #50
brewtus
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Originally Posted by UtahGuido View Post
Yeah, I've got to set aside some time to lay hands on this motor. The fact that it runs and is quite rideable has forestalled the urgency.

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Old 06-06-2013, 07:34 PM   #51
UtahGuido
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All things in good time. I'm trying to finish a deck rail right now. And for me "good time" might mean months. When I blew up the engine on my KLR it took 18 months before it was back on the road. Not that I'm boasting about that.
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Old 06-12-2013, 11:57 PM   #52
jonnyc21
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Quote:
Originally Posted by Twin-shocker View Post
It seems members of this forum are able to alter the laws of physics at will.............lower air density is something that occurs like it or not at higher altitudes, which will mean overly rich mixture on bikes jetted to run properly at sea level.

Any amount of chat room BS is never ever going to alter that fact, and it seems strange none of those suggesting the BS can alter things, are capable of using Google and finding out they are wrong?

I like how your so stuck on the facts of air density to fuel ratio that you can't get over the fact that your correctness doesn't take into consideration what others have also called out as facts around air density as it relates to the way the fuel circuits and jetting are also affected by that same low air density.

Just because your right about the facts of air density to fuel ratio doesn't change the simple fact that fuel ratio isn't the only thing your working with... get of your high horse and consider the bigger picture...

Truth: (weather you like it or not...!)
Quote:
Originally Posted by laser17 View Post
...FWIW: At very high altitudes - carbs circuits that utilize near ambient air pressure (pilot circuits) to push fuel through a small orifice can require a less restrictive fluid path to move an adequate amount of fuel when the "pushing" force (air pressure) drops. I think everyone assumes the carb works perfectly to maintain the correct Stoic ratio and the only thing that varies is air density. The air density also affects how the carb works! Carbs are usually designed to work at or near sea level, so severe altitude can create non- linear responses for a circuit design and hence the jetting adjustment isn't necessarily intuitive.
...
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Old 06-13-2013, 07:42 AM   #53
Twin-shocker
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Please feel free to provide a link to any serious technical information, which suggests carb jets need to be increased in size to compensate for lower air density at higher altitudes.

It seems astonishing that anyone would choose to make themselves look like a total idiot, by suggesting the laws of physics are subject to change, merely to excuse the fact they have made a silly mistake, by claiming jet sizes need to be increased, rather than decreased when running at higher altitudes!
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Old 06-13-2013, 11:35 AM   #54
ridenm
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Quote:
Originally Posted by Twin-shocker View Post
Please feel free to provide a link to any serious technical information, which suggests carb jets need to be increased in size to compensate for lower air density at higher altitudes.

It seems astonishing that anyone would choose to make themselves look like a total idiot, by suggesting the laws of physics are subject to change, merely to excuse the fact they have made a silly mistake, by claiming jet sizes need to be increased, rather than decreased when running at higher altitudes!
One more time. By failing to consider the starting point for a specific engine, you miss the big picture. Say you start with an EPA-lean engine at 3000 ft ASL. You take that engine to 4000 feet ASL. The altitude change has made that bike run richer than it was, but it was EPA-lean to begin with, so further richening may be called for to obtain proper mixture. Nothing has changed about the laws of physics, but the baseline conditions determine the course of action, not a textbook.
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Old 06-13-2013, 12:13 PM   #55
laser17
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As RideNM correctly states - Initial conditions are very important for any calculation whether Physical, Chemical or Comical...

Folks, Twin-Shocker is a very opinionated and very inflexible forum poster. Don't ever try to change his mind. But to be honest, I kinda like that about him. He does bring up some valid points, is helpful at times, and just because he could care less about what we have to say, and won't consider alternatives to his way of thinking - ever, doesn't make him a villain - just a character.

Side story: I remember when working in the disk drive industry, that we had to come up with an air bearing design that would maintain nearly constant physical/magnetic spacing as the transducer was "flown" across the surface of the rotating disk. Knowing that the relative velocity at the outer diameter of the disk was much higher than at the ID, I commented that it was like keeping a boat tied to the dock floating at the same height as the tides changed. Everyone knows you cant do that right? I was sure it couldn't be done.... well guess what.

laser17 screwed with this post 06-14-2013 at 09:37 AM
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Old 06-13-2013, 12:46 PM   #56
Twin-shocker
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Originally Posted by ridenm View Post
One more time. By failing to consider the starting point for a specific engine, you miss the big picture. Say you start with an EPA-lean engine at 3000 ft ASL. You take that engine to 4000 feet ASL. The altitude change has made that bike run richer than it was, but it was EPA-lean to begin with, so further richening may be called for to obtain proper mixture. Nothing has changed about the laws of physics, but the baseline conditions determine the course of action, not a textbook.
I would agree entirely that any motor which is jetted very lean in the first place, may not need compensatory changes for use at higher altitudes. However not sure that many TLR's are still likely to be fitted with OE jetting, or worn out OE carbs for that matter?
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Old 06-13-2013, 01:20 PM   #57
motojunky
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Quote:
Originally Posted by Twin-shocker View Post
However not sure that many TLR's are still likely to be fitted with OE jetting, or worn out OE carbs for that matter?
I think you'd be surprised at how often low-use TLRs pop up in the US. I've probably seen 5-8 in the last couple of years turn up with ~1,000 miles or less. And I'm not looking for them...

I think most TLRs sold in the US ended up stuffed in the back corner of garages.
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Old 06-13-2013, 10:00 PM   #58
lineaway
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So, twinshocker what is the greatest elevation you tuned a bike at and what fine bike might that be?














/
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Old 06-13-2013, 10:04 PM   #59
lineaway
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Quote:
Originally Posted by Twin-shocker View Post
I would agree entirely that any motor which is jetted very lean in the first place, may not need compensatory changes for use at higher altitudes. However not sure that many TLR's are still likely to be fitted with OE jetting, or worn out OE carbs for that matter?
Hmmn, did you ever take into account the carb on the usa version of the tlr200 had no pilot jets available?
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Old 06-13-2013, 11:10 PM   #60
jonnyc21
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Quote:
Originally Posted by Twin-shocker View Post
Please feel free to provide a link to any serious technical information, which suggests carb jets need to be increased in size to compensate for lower air density at higher altitudes.

It seems astonishing that anyone would choose to make themselves look like a total idiot, by suggesting the laws of physics are subject to change, merely to excuse the fact they have made a silly mistake, by claiming jet sizes need to be increased, rather than decreased when running at higher altitudes!
I am not disagreeing that the bike needs less fuel, just that the concept of a smaller jet being the correct direction to get there on every carburetor. Not all carburetors are designed equal...

I would hope that everyone would agree that a pilot circuits requires air pressure to work correctly and if the air pressure drops it would then affect the flow of the fuel/fluid in that circuit.

Considering the drop in pressure from sea level to 6000 feet is 20.1kPa (2.9psi) and sea level to 9000 is 28.6kPa (4.15psi), it is quite possible that a circuit designed to operate at sea level could be to restrictive at that pressure and require a larger jet to get the proper mixture.

Pressure chart: http://www.engineeringtoolbox.com/ai...ure-d_462.html

Hope this clears up my stance a bit...
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