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#143825 - 06/30/08 12:29 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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JTsmks Offline
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Orange Park Florida
I'd put two 6 volt coils and Champion N5C's on the thing and see how that does it. I feel all the carb work has you running in circles, I'd pitch that harley coil over to someone who rides a harley. I don't feel at this point the carbon fouling is a carb result, I know I've been there. Just the wrong heat range and non-solid copper wires were killing my plugs (N3C as under the seat + silicone wires...damn PO!) I could be wrong but then again two asian 6 volts won't run you much, neither do N5Cs. All IMHO smile


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#143826 - 06/30/08 1:51 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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highway Offline
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hamilton on. can.
There is nothing in the tuning of the AMAL MII, T140s that should require plugs two ranges hotter than the earlier T140. The compression was dropped to 8.2 from the earlier 8.7, but other than that it is just a 1973 to 1978 TR7 head with two intake stubs fitted. The operating temperature did not decrease significantly to warrant it, and most now have the higher ratio fitted. An English rode test of the day stated Triumph fitted them to reduce fouling and stated the bikes carburation seemed rich.
Most we got in had the pilot and enricheners jets reduced in size and some required more cutaway from new. The bikes ran cleaner, better and had improved gas mileage. (important on a small tank machine). Once sorted N3 plugs were used.
I had a customer ask for N12y plugs for his commando years ago. I told him they run N7y, to which he replied the 12s work better in his bike as the others don't last a couple of days, He rode off leaving behind a haze of blue smoke. Going up one range on a tired engine is not usually a problem, by going higher can result in holed pistons at highway speeds.
I think you should try #20 pilots, as the bike seems to be much closer to correct. I don't know how the 405 plugs relate in heat range to champion but I would think they are probably hotter than they need to be. Rick

#143827 - 06/30/08 2:16 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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aprophet Offline
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Chesapeake Virginia
looking at a NGK cross referance it looks like 405 is the equivelent of champion N-5 before i got my electics sorted my A65C would not run on anything but champions i had to change plugs a coupla times to belive ithope you figger it out beerchug


1964 A65C Rocket (Jeanie)
1971 T25SS
1971 A65T BSA (Lucile)
1965 A65D Lightning Rocket
#143828 - 06/30/08 2:44 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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JTsmks Offline
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Orange Park Florida
1979 and up T140D and T140E takes Champion N5C or equivalent. Earlier T140V takes N3C. Highway you are fully entitled to your take on the subject as are all that read and post here. I'm just stating what comes from the manufacture and from Champion themselves + in my stock set T140D it carbon fouls N3Cs and runs just fine on N5Cs as recommended by the manufacture, so far many a thousand miles and no fouled plugs and no holed pistons.

NGK lists the B8ES for T140V and B6ES for T140D and T140E.
Champion lists N3C for T140V and N5C for T140D and T140E.


"All parts falling off this bike are of the finest British craftsmanship"
#143829 - 06/30/08 3:05 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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Mark Z Online content
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Owego, NY, USA
Sawtooth: "ignition - stock electronic - not Boyer".

Ok? Lucas Rita ig., not points!

So we think that stock jetting should work with 1.75 open pipes?


Mark Z

'65(lower)/'66(upper, wheels, front end, controls)/'67(seat, exhaust, fuel tank, headlamp)/'70(frame) A65 Bitsa.
#143830 - 06/30/08 1:09 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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sawtooth Offline
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New York
mom! dad! please don't fight ; )) (re: plugs)

my take on the plug subject is that...contrary to popular belief..the autolite might just be a better plug...i have no evidence to support this other than the 4 autolites that i have been using on and off since the this nightmare began vs 20+ ngk/champs...i have collected in a box..i've cleaned them and attempted to reuse them and they work but not for long...this in contrast to the autolites which keep on performing

now unless there is major difference in heat range (fyi my research has showed that that the 405 is equivalent to a N6..but this thread suggests that they are equivalent to N5) the autolite must just be a better plug

ok..back to business

so whats my next step??

pilot jets? (ie #20's)

or attack the iginition? (which is not a points setup - transducer/reluctor/magnet/amplifier (Lucas)

#143831 - 06/30/08 1:51 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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John Healy Online content
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"There is nothing in the tuning of the AMAL MII, T140s that should require plugs two ranges hotter than the earlier T140. The compression was dropped to 8.2 from the earlier 8.7, but other than that it is just a 1973 to 1978 TR7 head with two intake stubs fitted. The operating temperature did not decrease significantly to warrant it, and most now have the higher ratio fitted. An English rode test of the day stated Triumph fitted them to reduce fouling and stated the bikes carburation seemed rich."

Wrong!
John


#143832 - 06/30/08 7:00 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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triumphmike Offline
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Tennessee
sawtooth,

Let's step back for a second and look the big picture. Two of the items you mentioned above really stand out to me:

1. Ran poorly above 1/4 throttle - this really points to the needle and needle jet (ignoring the fouling problem for the moment). Above 1/4 throttle the pilot jet has little or no influence with the carburation.

2. Running 1 3/4" open exhaust pipes - little or no back pressure (which mufflers provide to varying degrees) usually means carbs must be tuned richer (engine want more fuel).

IMHO your needle jet SHOULD be a .106 and your needle a 2A1 (assuming all else is 100%). However your plug fouling problem infers the engine is running too rich which is contradictory.

I have a T140D with an a single Accel 3 ohm coil and a Boyer. The Lucas Rita ignition was giving me problems and, once I replaced the stock coils and ignition, it runs exceptionaly well (3.5 slide, .106 needle jets, 2A1 needle center notch, #15 pilots, #20 chokes). The exhaust is the original 2-into-1 system but I replaced the original muffler (read "boat anchor") with a SuperTrapp. I am also using B7ES plugs.

After a long way around the barn, I would recommend you replace your Rita ignition with a Boyer, but based on the info you provided as to the rest of the setup I think you will still need to tweak.

#143833 - 06/30/08 7:05 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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JTsmks Offline
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Orange Park Florida
ST, If it were me (and it isn't) I'd pitch the Harley coil in trade for two 6 volts, replace the plugs with NEW N5Cs (people here talked me back to champions and I haven't regretted it) or equivalent and make sure your running solid wire wires. Alot of problems in the primary and secondary ignition system go toward carbs at times. I've no doubt you had carb issues but I think you've rebuilt and resolved. Now get the ignition to square one, timing set, carbs adjusted to base and see where you are.


"All parts falling off this bike are of the finest British craftsmanship"
#143834 - 06/30/08 10:16 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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az-idea Offline
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palo alto,ca.
..Gotta confirm Saw's Conclusion on Autolites when in the Dark Tuneing phase..They eat Champs\NGK's For Brekfast..Way more Robust and reliable..However,I Agree 405[N5\Ngk6]is too hot..Stick with 404\AP64's...Just noticed you Run"open"1 3\4"pipe..Youll want a"key"style insert at the end[s]for back pressure[adjustable angle vs flow] to get proper top end or,they will scavenge most of your cylinder charge at upper range if left Open..Disagree that at 1\4 throttle your off pilot..theres overlap even into 3\4...vice versa the Main will,if too big,affect lower throttle..overlap is something to always keep in mind!...Time to try 20 pilot...and possibly..to step down the needle jet..You run open pipe..They may Burble at Idle..but once under throttle they pull on the jets more and you[as your discovering]need to lean from Standard jet sizes..IMHO..and..stick with the COIL YOU HAVE..for now...

#143835 - 06/30/08 11:51 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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sawtooth Offline
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New York
i guess my objective at this point is to get it running consistently and better...i am not expecting perfection at this point...i just don't have the $$$

i just spent $250+ on carb parts and would prefer not to re-purchase the same parts again (ie .105 vs .106)

but i can't imagine #20 pilot jets to be all that expensive

i am going to stick with coil i have for now..i do have the accel coil that came with bike but ..again...the harley coil is new and i don't want to go back out and buy yet another new coil setup...yes it may be THE best thing to do...but unless i come into some money..i will have to stick with what i have

and please understand..its not that i am being cheap..its just that i have invested way too much money into this project...and if it wasn't for my zeal to finish something that i start and need to make things "right" this bike would have been eBay'd many months ago

my paid friends are insisting that i get a Boyer..there no evidence to suggest that its a must have but basically the ignition system is the only system on the bike that hasn't been replaced or reconditioned

i did pick up a "ignition spark tester" today (one end is inserted into the plug...there is a clip which goes to ground and its adjustable from standard, electronic & 2-4kV) as highway noted this might give me a better indication of what is going on with the ignition system

unless anyone can suggest otherwise i will start saving for a Boyer and pickup the #20 pilots

just another $150+..i keep telling myself that i've gone this far...whats another couple of hundred...i don't know just seems like there is no end in site..i guess if i was smart and not so obsessed with making things "right" i would just sell the albatross and be done with it

and i might as well buy a set of 404's while i am at it..

mr. tooth

#143836 - 07/01/08 12:30 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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JTsmks Offline
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Orange Park Florida
Holycrap, I didn't relize my Rita ignition was such a piece of junk. I'm going out and taking a hammer to it pronto! I can't believe I ever went out on the open road with it! wink


"All parts falling off this bike are of the finest British craftsmanship"
#143837 - 07/01/08 1:11 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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sawtooth Offline
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New York
I don't know if they are junk or not...but my experience with this turd is any indication i am sure MINE is junk : )

#143838 - 07/01/08 1:13 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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Steve in Tulsa Offline
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Tulsa, Oklahoma, USA
I sent my spare Rita amp to Mistral Eng in England for a rebuild. I have a Boyer in my 78 T140V and I am swapping them out. I have no problems with the Rita. I'll sell the Boyer before too long.
----
More dumb questions. Are the plug wires getting bare spots and grounding on the head? Are the connections good at the rectifier?
It must rev to 3600 to set the timing under no load.
Are the needles free in the pilot jets?


Steve in Tulsa
#143839 - 07/01/08 1:22 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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John Healy Online content
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Boston, Massachusetts
Thought I would share some info from my collection of letters. This might clear the ari about Champion N5 plugs in teh T140E models.

The Champion N5 spark plugs are the perfect heat range for this motorcycle. If you are unable to burn off the carbon with the N5's anything cooler would just foul quicker.

Please remember that these comments by Brian Jones refer to the 1979 models. They were struggling to meet EPA requirements and these carbs were, if anything, set up at the factory LEAN to pass rigid emmsion tests. Modifications made by US dealers, including modifying the carb to UK specifications, were to make them run a bit richer.


[img]http://members.aol.com:/triumphownerclub/app00711[/img]

[img]http://members.aol.com:/triumphownerclub/app00722[/img]


#143840 - 07/01/08 1:54 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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az-idea Offline
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palo alto,ca.
Forgot for Stock T140\detuned Cam..N5 is Best..Take Johns word on that..[but stick with the Autolites..!]..your pilots will be cheap Btw..and Check M.A.P if you decide to 105NJ..[think $15 apiece]..

#143841 - 07/01/08 5:56 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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John Cahill Offline
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Sedona, Arizona
hi, sawtooth
not sure if this helps or not...but I have pretty much the same bike, same setup and had the same sooty plug problem until I changed back to stock mufflers. On the other hand though, I am at 4300 ft elevation. I know conventional wisdom says that straight-through bikes meed more fuel...but in my experience it went the other way round. I am oversimplifying a bit, and did in fact change out virtually every bit of the carb as well (although sequentially..noting the changes as I went)...but I definitely noticed less carbon fouling swapping back to stock pipes. Just a thought. Also, my first set of new 2C3 needles were actually tapered wrong and too rich...another consideration.
regards,
John


1979 1/2 Bonneville T140E
1993 Mazda Miata
2001 Jeep Wrangler
#143842 - 07/01/08 11:36 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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JTsmks Offline
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Orange Park Florida
My T140D has 1 1/2" MAP aftermarket pipes and low restriction aftermarket mufflers, the carbs are bone stock MKIIs, I've no fouling problems with the stock ignition and N5Cs. I did have plenty of fouling when I ran silicone wires and N3C/B7ES.


"All parts falling off this bike are of the finest British craftsmanship"
#143843 - 07/01/08 1:05 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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sawtooth Offline
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New York
ok...so i will keep working with my autolite 405's ~ N5/N6?

i am serious when i say that these plugs just keep on working (knock on wood)..fouled or not..they just keep working vs. ngk/champs which fouled and died ....cleaned ..and then they would die again in 5-10 minutes

pipes: i agree this is part of the issue (ie back pressure)

but its been my experience that if you modify the exhaust to be less restrictive then you need to modify the intake as well..so it too less restrictive - that is why i pulled my air cleaners initially and the bike did perform better (see other threads) air cleaners are currently installed...breath out easy - breath in easy.

so now i am going to go out and purchase purchase a new set of 404'S & 405's (or maybe not... the wife is getting sick of me buying plugs..yes i am cleaning/re-using....the ngk/champs are destined for a decorative wind chime)

i will test the spark intensity with my new fangled spark tester and report the findings

and that will have to be it for now becuase thats all $$ i have at this time...but my wish list includes #20 pilot jets and a Boyer ignition.

#143844 - 07/01/08 7:10 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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sawtooth Offline
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New York
i wonder if a could rig up some form of screen (yeah and kill the engine in the process) on the carb air intakes and ditch the stock air cleaners?

i bet nickels for nightmares that a "high performance" air intake/setup would improve the running/performance

..tunner 101

#143845 - 07/01/08 8:16 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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highway Offline
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hamilton on. can.
I was WRONG, The comp ratio dropped to 7.9 on ES models.
However, If the parallel port head runs that much cooler to need plugs 2 heat ranges colder than the splayered head T140. (The splayed head loses some finning with the ports farther apart).One could assume the Tr6 and the TR7 would also need a colder plug than the one fitted to the T120 or the T140 (to 1978)
I don.t believe they run THAT much colder. I also believe a Concentric carb TR7 would under the same tune and conditions have survived the testing with n5 plugs with similar results, and if the air screw was turned in a half turn too far, OR. the slide cut away 1/2 size to small it too would have benefitted as the t140e did, with its richer than needed, pilot and starting circuit. The fact that they mention the N5 plugs are "more forgiving" to rich starting mixture, I can't help to think if 25 starting and 20 pilots were used in the test bike, Being "more forgiving:" wouldn't have been an issue.
Although this letter was written in 79 we were still getting from the factory in 1983 bikes with the same rich, around the town, carboning up that we had in 79.
I have used N3 and n4 plugs in Bsa and tri. twins for years Including T140D and T140es and found, as the test did, a benefit in using N5 plugs.......until the pilot size and/or slide cutaway were corrected.
One must also consider when selecting main jet sizes and plug heat range that todays and tomorrows gas is not what it iused to be. Lower octane, ethanol, methanol. etc. can lead to mixture changes, pre ignition, detonation, heat spiking . Running a plug just hot enough to burn clean in a properly jetted engine, is a safer bet than running a hotter plug to cure low speed richness, or an oil burning issue.
Of coarse this is my own humble opinion. RICK

#143846 - 07/01/08 9:46 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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John Healy Online content
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Boston, Massachusetts
Highway:
I tried to respond to this, but after typing for an hour and making several links to sites that discuss modern gasoline I deleted it all when I got this flash.

I think the graphic that sums up MHO = :rolleyes:

It ain't about the fins, it is about combustion efficiency!

www.fefcholden.org.au/techinfo/BPFuels_PET2002.doc

BUT none of this helps Sawtooth!!!!
John


#143847 - 07/01/08 10:38 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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tomterrific Offline
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Columbus, Ohio, 1978 T140E
I gave my MKII jetting changes somewhere. They are very much similar to Steve's except... I used the #25 jet in the enrichening circuit, the #15 pilot jets AND I pulled out the air correction jets.

I spent the coin to get the enrichment lever on the handlebars. I love it. The #25 jets make it a less on-off sort of system and more of a fast idle. I think I could get away with #20 jets in the enricheners and it would be smoother with the choke on.

A Boyer needs the throttle blipped to 5000rpm to check full advance. The Lucas Rita?

A straight through exhaust may have reversion problems through the carbs. This is where a strong positive signal goes back up the exhaust during valve overlap. It will run as rich as a river at this point in the rpm band. Straight through exhaust doesn't work so well for a street bike.

I've heard the parallel port heads have a lot of swirl in the CC. Larry Widmere's theory on both why he could run diesel compression ratios and extremely lean mixtures on his high swirl NASCAR engines was that the fuel tended to concentrate in the center of the combustion chamber. This gave a natural stratified charge. I wonder if this is something happening in the T140E head to make it seem to run rich? Bathing the plug tip in a rich mixture.

If the intake mixture is directed at the spark plug tip the plug will run cooler. This may be another reason the T140E heads need a hot plug. The plug itself is running no hotter than a two step cooler plug on an older splayed port head. IOW, the N5C in the parallel port head runs the same temperature as the N3C in a splayed port head. Don't know, just speculating.

Tom Graham

#143848 - 07/01/08 11:58 pm Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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Steve in Tulsa Offline
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Tulsa, Oklahoma, USA
Tom, I did remove the 'top hats'( air correction jets). I just forgot to add it.
I always thought the parallel port head has poorer flow characteristics, there is a head bolt in the way on the intake port, than the splayed port so a hotter plug is needed as a fix for a more complete burn. It's like the Chevy spark tracking of the 80s. A quick fix for poor CC design. If not mistaken Widmere's intake design is very sophisticated leading to excellent flow characteristics
and atomization. But NASCARs are always a top revs as well, yes?


Steve in Tulsa
#143849 - 07/02/08 12:06 am Re: 1979 T140E - Amal MKII - Plug Fouling TURD  
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John Healy Online content
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"A straight through exhaust may have reversion problems through the carbs. This is where a strong positive signal goes back up the exhaust durring valve overlap. It will run as rich as a river at this point in the rpm band."

This can be seen on a dyno run when you connect a gas ****yzer to the dyno computer. You can match the drop in hp with the momentary richness. This is a much bigger problem with megaphones.

Keven Camneron discussed the effects of parallel ports on the T140, the "swirl effect" and resultant lower combustion temperatures in a previous issue of Vintage bike. But this is not going to fix Sawtooth's bike.

"The plug itself is running no hotter than a two step cooler plug on an older splayed port head. IOW, the N5C in the parallel port head runs the same temperature as the N3C in a splayed port head"

Yes, if it ran hotter there would be problems. Below 850 degrees F and carbon begins to collect on the plug. Approaching 1500 degrees F and the metals and ceramic start to fail. The aim is to keep some where in between these temperatures.

But again, while interesting it does not solve Sawtooth's problem.

Now sawtooth is running a .105 needle jet. That jet with a 2C3 needle should be lean from just above idle to nearly half throttle, or above. NOT RICH. So what are we not seeing?

Please note that I think Steve has removed his air correction jet as has Tom. This will also lean out the mixture as it reduces the signal on the jets.
John


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