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Old 01-10-2014, 08:00 AM   #46
t_g_farrell
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Quote:
Originally Posted by fbRXse7en View Post
Nice! You got the idea there. I just got some primary and secondary jets to
use in tuning mine better now. I'm pretty sure I drilled the primaries way too
large at this point. I'll back them down to near stock, throw it on soon and see
how it runs.






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Old 01-10-2014, 11:47 AM   #47
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Quote:
Originally Posted by t_g_farrell View Post
Nice! You got the idea there. I just got some primary and secondary jets to
use in tuning mine better now. I'm pretty sure I drilled the primaries way too
large at this point. I'll back them down to near stock, throw it on soon and see
how it runs.
Thx, gotta love the internet! Here's more..
http://www.youtube.com/edit?o=U&video_id=LeVoPaxffu0
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Old 08-03-2014, 04:01 PM   #48
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Talking Got it done and running

Ok, finally got the carb on and running perfect. Had the following issues to resolve:

1. Flooding on startup - had to find a true 12V ignition source for the FBVS so it would
click on when the key was engaged.

2. Vaccum leaks - Found a big tube above the MAS I forgot to plug and the hot start
assist port needed to plugged.

3. Idle circuit not working - Original carb had the air bleeds swappped on the
primaries and secondaries. I'm sure I didn't do this because I am pretty careful when I disassemble a
carb to not swap things around. BTW this is an 84 carb.

So addressed all those issues and replaced my drilled out primaries with 95 jets I got
from Mazdatrix. Set the MAS to 3.5 turns out and the idle to barely open the primaries.
Put it back on and fired it up. Ran but needed adjustments.

Had to adjust the choke cable to the fast idle linkage and had to relax the throttle cable
a bit. Then proceeded to play with the MAS and the idle until it was down to 800 rpm
and idling as good or better than the Dell.

Took it out for a test drive and boy is this thing a blast. Rips to redline as soon as the
secondaries kick it. Did I tell you the secondaries kicked in, lLIKE A MULE! Tons of fun
and have to kind of learn to drive with it since I've been using the Dell for over 20 years
now.

Heres the interesting bit. I took it to the gas stationed, filled it up and then proceeded to
drive my 55 mile mileage check loop on the interstate. Its all interstate with one exit
to loop around and come back home. 27.5 miles each way. I cruised at 75 mph 80% of
the way and then had to kick down to 65 as it goes down to 55 right about where I
make the turn around. Returned to the same pump at the same station, filled it up again.
It took 1.787 gallons and I was careful to fill up to the same measure as before. Basically
held it until it kicked off and the topped it up by 3 cents to the next 5 cent
mark. Did it this way on both fillups.

And the final numbers were 55/1.78 = 30 mpg. Thirty freaking miles to the gallon. I think
its safe to say I'm running lean. I have jets now to make it richer. Interesting the engine
didn't seem to run really hot or anything but at that mpg its got to be lean. This is with
stock jets for everything but the primaries. Stock would be 92 and I have 95 in there.
I bet I can go up to 100 or 105 without a problem.

Big shout out to Jeff20B for some IM discussions we had over the last few months.

Hmm I better fix that signature now ...
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Last edited by t_g_farrell; 08-03-2014 at 04:21 PM..
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Old 08-03-2014, 05:12 PM   #49
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Glad to hear you got it figured out. The Nikki is a really cool little carburetor.
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Old 08-03-2014, 07:55 PM   #50
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Quote:
Originally Posted by GySgtFrank View Post
Glad to hear you got it figured out. The Nikki is a really cool little carburetor.
Yeah it only took 2 years. Can't wait to really tune it.
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Old 08-03-2014, 08:00 PM   #51
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Quote:
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Yeah it only took 2 years. Can't wait to really tune it.
Using oxygen sensors? Or doing it the old fashioned way by reading the plugs?
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Old 08-04-2014, 07:27 AM   #52
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Quote:
Originally Posted by GySgtFrank View Post
Using oxygen sensors? Or doing it the old fashioned way by reading the plugs?
I have dual bungs on the RB SP exhaust right before they join the rear section so
I would like to get a dual AFR meter and set it up.

For now I'll just do it the old fashion way. I can probably get the primaries
pretty close that way.
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Old 08-07-2014, 04:02 PM   #53
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I'll go ahead and put the 105 in for the primaries and up the secondaries to 170 and see
how it flies. I'll tune for plug color from there.
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Old 08-07-2014, 04:10 PM   #54
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Oh I forgot to mention that I ended up pushing the oil tubes back in close to the primary
venturis so the oil gets atomzed better into the air fuel mix. Based on some feed back from
a conversation I was having with Jeff20B on the other forum.
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Old 08-08-2014, 08:56 AM   #55
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Put the larger jets in and big difference. Still haven't looked at the plugs yet. Did retune
the MAS adjustment and that worked much better now. I tuned it out rich and then back
in some so I know its a slightly richer mixture. Put my idle right at 750 or so.

The throttle seems to stick a bit and not fully return after its been used. I'll have to see
whats making it stick or bind. Makes my idle jump up to about 900 or so as I drive
around.

The secondaries kick in with a vengeance and little late maybe. I'll play with that some
more as well. When pushing the pedal you can feel a stop when you get to the
secondary activation and you have to push through it. No real hesitation just extra
effort to push down the pedal. Makes it really easy to stay out of the secondaries but
can be a bit jarring when you mash the pedal. Also a lot of fun!!

Can you tell I'm having fun with this finally?

I'll do a mileage run again and see how bad I've made it now. I'm pretty sure it won't be
30 mpg this time.
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Old 09-26-2014, 12:16 PM   #56
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Made run to RTP yesterday to go to my office. On the way there I did a fillup at the end
and I saw 23mpg cruising 70 to 80mph for about 150 miles of interstate. I check before I
left and when I filled up it looks like around town I'm seeing ~20mpg.

So the new jets have definitely richen the mixture and I think its tuned about right.

The secondaries still kick like mule and will break traction easily in most gears except
5th. I may work on those at some point but its a lot of fun at the moment.

I'd like to get an air cleaner that fits the carb (4 1/4" seems about right). Right now I
have the stock air cleaner with the snorkel pulled off. Looks kind of rigged if you know
what I mean. I'd like to find an air cleaner base that will work with the stock top diameter
and then just drill a hole thru the stock top to bolt it on instead of using the clips.
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Old 09-06-2016, 02:27 AM   #57
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Hi t_g_farrell. I'm the guy with the campangolos that you commented on a few months back. I just saw this thread and I'm glad I did. I know it's an old thread but...Quick question. I've got an 81 Nikki. Will your mods (basically) work with this carb? Planning the mechanical link set up for the butterflies...the AP double gaskets. Don't need or want too much HP as I need the reliability.
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Old 09-06-2016, 07:36 AM   #58
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Yeah I'm pretty sure it will work the same for any year nikki. Especially for FB nikkis which
are all pretty much the same. The series 1 nikkis are a bit different in places. Good luck
with your mods.
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Old 09-07-2016, 02:51 AM   #59
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Many thanks t_g_farrell. I hope you don't mind if I pop in a question or 2 as I go along.
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