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2T oil/fuel ratio and spark plug colour

Posted: Fri Aug 11, 2017 9:43 pm
by LC Cnd
Mikuni 26 carb's, mains 230/pilot 27.5/needle stock setting (middle) on Micron pipes. Using 94 Chevon octane with Amsoil Interceptor at 40;1 ratio. Pulled the pugs(ngk br8es), after 500kms and they still look too far on the rich side although on the porcelain I do see a hint of dark chocolate color. Should I go to 50:1 (with Amsoil apparently you can) or lean it out with the needle at which setting? Side note: she does pull at 6000 nicely but it appears there is more according to the colour.

Re: 2T oil/fuel ratio and spark plug colour

Posted: Fri Aug 11, 2017 10:02 pm
by hondaror
Your porcelain has to be read way down. Looks really rich. Try raising the needle by dropping the clip one notch.

Edit:dropping the needle by raising the clip one notch.

One thing at a time without the dyno, only one.

Re: 2T oil/fuel ratio and spark plug colour

Posted: Fri Aug 11, 2017 10:10 pm
by T.RexRacing
That's not oil on the plug-it's fuel. She's fat. Start with the pilot and work up to the main. Go easy and buy a box of plugs. Too bad yer way over there. I have a nice dyno cell at my disposal.

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sat Aug 12, 2017 1:36 am
by LC Cnd
Considering what it took to get to this pt, a box of plugs is an easy investment. Now a dyno cell - thats not an easy investment fm what I note on youtube. Just started driving her to work this week: no issues starting first kick with the choke out then idling down to 1100-1200rpms. Never practiced chopping plugs b4 but I'm teachable and got a hacksaw hanging on the shop pegboard. Agreed, she's running way fat; time to make her lean (er) n' mean - meaning, I'm impressed with the current power band but frankly I can't imagine what she'll will be like once light tanned plugs occur - I'm imaging a scary ride however in a good way. Off to Lordco in the AM to see if they have any br8es's left - cheaper than Cnd Tire.

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sat Aug 12, 2017 3:15 am
by hondaror
Scott, 1UA's? Get B9ES's, 31K-B8ES's.

Plug chops are only for your main jets.

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sat Aug 12, 2017 1:35 pm
by LC Cnd
Bought a box of B8ES (10) @ $36 so I have 5 opportunities to dial in to start. I have main jets fm 160 to 240. The lowest I've got for pilots is 25. Plugs arrive tomorrow. I'll start with the needle adjustment first then move on to the jets for this trail and error adventure (rural solution - no dyno).

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sat Aug 12, 2017 4:05 pm
by JanBros
no point in checking plugs afer 500km's, as you only diagnose the last 100 meters the engine was running. to use plugs as a diagnose, you need to run a specific situation like WOT, cut the engine and pull the clutch, stop and immediatly check the plug. than you have an idea if the main jet is ok.

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sat Aug 12, 2017 5:54 pm
by winner_evo
If they are 4L0 -01 carbs with genuine nozzles then the correct pilots are 22.5. How many turns on the air screw are you?

Obvisously a different part of the world but here in the UK a 22.5 pilot is pretty rich on an LC and no need to go bigger even with a fair bit of tuning.

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sun Aug 13, 2017 10:25 am
by TCRZ88
You should be running BR9ES plugs. The BR8ES are too hot for the RZ. Possible head damage can result.

Sent from my LG-H831 using Tapatalk

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sun Aug 13, 2017 12:25 pm
by T.RexRacing
You sure about that?
plugs2.jpg
plugs2.jpg (37.27 KiB) Viewed 5424 times

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sun Aug 13, 2017 3:17 pm
by LC Cnd
The manual states NGK B8ES. Yes 22.5 is correct for the pilot but I was having toubles with starting her with this size; 27.5 appears to be the one that works interestingly. Might have something to do with the Microns - don't know. Again it 27.5 could be causing the fatness on the spark plugs but she starts no problem. So, whats the proper proceedure for plug chop other than the last 100 meters matter?

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sun Aug 13, 2017 4:06 pm
by T.RexRacing
They always start easy fat. Try a 25?

IMHO the resistor plugs work just as well as non-resistor with the benefit of not screwing with ignition or nearby radios. I've had racebikes with MSD ignitions,copper wires and non resistor plugs screw with the computer bad enough it aborted dyno runs.

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sun Aug 13, 2017 8:20 pm
by LC Cnd
Raised the needle one notch and the bike would bogged out on acceleration. Start up was also difficult. The only time acceleration or start up work was when I engaged the choke.

Re: 2T oil/fuel ratio and spark plug colour

Posted: Sun Aug 13, 2017 11:40 pm
by LC Cnd
Update: change all jets and carb settings all to stock spec to baseline this matter and got the new spark plugs. Read on RDLC Crazy that stock specs work fine with aftermarket pipes. Start up was fine. Went for a test run this evening - did not note any dif between the 220 and the 230 mains regarding the power band. Whats next to make her run less rich?

Re: 2T oil/fuel ratio and spark plug colour

Posted: Tue Aug 15, 2017 1:22 pm
by Bare
Temporarily(?) remove the airfilter box's cover .