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Two Brothers Headers installed. Bike runs too lean - Help!

Started by thevalkdude, Sun 23, May 2021, 23:37:57

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thevalkdude

Installed the 6 in to 6 pipes on my 97 Stock bike. I know the bike is for sure running lean. Plugs are white as when they were new!

My Air Bleeds Screws are about to fall out - 4 plus turns out!!

Anyone have guidance on which jets to use for this set up? I have a 97 Stock Black on Black. No other mods.
Thanks a bunch.

Leathel

you could try lifting the needles by putting a shim under the needles..... can do it with carbs in easily

Chrisj CMA

If you are running a K&N air filter those lean out the mixture. Going back to OEM could help

98valk

Quote from: thevalkdude on Sun 23, May 2021, 23:37:57
Installed the 6 in to 6 pipes on my 97 Stock bike. I know the bike is for sure running lean. Plugs are white as when they were new!

My Air Bleeds Screws are about to fall out - 4 plus turns out!!

Anyone have guidance on which jets to use for this set up? I have a 97 Stock Black on Black. No other mods.
Thanks a bunch.


with today's gas, plugs will usually be white. so almost impossible to read plugs today, the old pics of plugs running on leaded gas do not apply.  u are not running lean. 
1998 Std/Tourer, 2007 DR200SE, 1981 CB900C  10speed
1973 Duster 340 4-speed rare A/C, 2001 F250 4x4 7.3L, 6sp

"Our Constitution was made only for a Moral and Religious people. It is wholly inadequate to the goverment of any other."
John Adams 10/11/1798

MarkT

Quote from: 98valk on Tue 25, May 2021, 09:43:34
Quote from: thevalkdude on Sun 23, May 2021, 23:37:57
Installed the 6 in to 6 pipes on my 97 Stock bike. I know the bike is for sure running lean. Plugs are white as when they were new!

My Air Bleeds Screws are about to fall out - 4 plus turns out!!

Anyone have guidance on which jets to use for this set up? I have a 97 Stock Black on Black. No other mods.
Thanks a bunch.


with today's gas, plugs will usually be white. so almost impossible to read plugs today, the old pics of plugs running on leaded gas do not apply.  u are not running lean.  

I haven't heard or seen that, about not being able to read plugs due to gas (or anything, actually).  But one thing is certain - and that's CHANGE.  (Little stays the same.)  The useless EPA creates lots of problems, including forcing vehicle makers to set them up to run lean.  Even if you do no mods.  Especially at low altitude.  He is for sure running lean even before dropping backpressure with his 6-6 "drag" pipes, if the bike hasn't been rejetted.  Typical is 17-1 even with OEM pipes.  Optimal is more like 14-1.  He is likely even thinner than 17-1.  A good dyno guy could confirm it but I think plugs can be read.

Of course he would be much better off if he can get pure gas.  Murphy's chain sells midgrade pure.  Don't know their distribution however.  I always buy that even though midgrade is unneeded for most of my vehicles.  Though my blown bobber requires premium so I have to use the ethanol crap.  Find pure gas stations in your area with this link - https://www.pure-gas.org/

Vietnam-474 TFW Takhli 9-12/72 Linebckr II;307 SBW U-Tapao 05/73-4

98valk

https://jetsrus.com/FAQs/FAQ_spark_plugs.htm


I've had my bike on a FactoryPro dyno with four gas analyzer.  Plugs were almost white even running pig rich at WOT at 10:1 ratio.
midrange to idle my ratio was spot on, plugs showed very little color.
1998 Std/Tourer, 2007 DR200SE, 1981 CB900C  10speed
1973 Duster 340 4-speed rare A/C, 2001 F250 4x4 7.3L, 6sp

"Our Constitution was made only for a Moral and Religious people. It is wholly inadequate to the goverment of any other."
John Adams 10/11/1798

RustyValkry

I'm not commenting because I know the subject, rather because of what I found when I started working on the RustyValkyrie. 

The PO had a set of TBR 6 into 6 pipes for the bike.  They weren't mounted but they came with it.  There was a set of stock pipes on it.  When I went through the junk in the saddlebags I found the kit pictured below.  When I tore down the carbs I confirmed the Cobra needles and springs were installed.  The jets were stock.  Since I had the stock pipes on I thought I might put the carbs back to stock but I discovered one of the needles was missing so I just left the kit installed.  Dynojet kits are pretty common in the Harley world, I was surprised to see one with my bike.

Someone's suggestion to shim the stock needles might help but like I said, I'm not knowledgeable about carbs.  I successfully rebuilt mine but that's easy compared to tuning them..


CoreyP

That about what I got with my bike and no way to know exactly how the bike was setup. It runs well so I don't fool with it. Bike came with truck stack glass pack exhausted install.

RustyValkry

#8
Quote from: CoreyP on Thu 27, May 2021, 21:19:03
That about what I got with my bike and no way to know exactly how the bike was setup. It runs well so I don't fool with it. Bike came with truck stack glass pack exhausted install.

I wanted to get the dynojet kit out so I could start with a stock carb setup.  My bike seems to run rich so it might well be the dynojet kit that's causing it.  I seem to recall it would cost something like $26 for one stock needles, so I decided against it.

BTW, for the OP, the Dynojet kits are still available . . . and pricy in case you wanted to consider that route.  As I said before I'm not knowledgeable about tuning carbs and can't endorse that route but it's possible.

98valk

Quote from: RustyValkry on Fri 28, May 2021, 09:58:48
Quote from: CoreyP on Thu 27, May 2021, 21:19:03
That about what I got with my bike and no way to know exactly how the bike was setup. It runs well so I don't fool with it. Bike came with truck stack glass pack exhausted install.

I wanted to get the dynojet kit out so I could start with a stock carb setup.  My bike seems to run rich so it might well be the dynojet kit that's causing it.  I seem to recall it would cost something like $26 for one stock needles, so I decided against it.

lower the needles by moving the clip up one notch to lean it out.
1998 Std/Tourer, 2007 DR200SE, 1981 CB900C  10speed
1973 Duster 340 4-speed rare A/C, 2001 F250 4x4 7.3L, 6sp

"Our Constitution was made only for a Moral and Religious people. It is wholly inadequate to the goverment of any other."
John Adams 10/11/1798