Britbike forum
Posted By: reverb carburetor, phases, road tuning - 12/18/17 4:03 pm
...hello, an hour ago I took the road to perform that dangerous main jet tuning (also attacked by killer bees! now I have the head inflamed in some spots)

-Spark plugs are Champion L87 due to work better in my bike than the L82.
-Magneto is a Hunt.
-Carburetor is a 626 with the thicker O ring that I brought a year ago with homemade filter due to no space in the 48s models for a proper filter; however, never had a problem with this filter and I am using it since 20 years ago.
-no goo on the jets.

-In this country there are only 2 types of fuel. One is "premium" for the new cars then the other is "super" for the rest. About 10 years ago was "normal" that was what I used for the bike.
I think super is 95 and the other is 97 (or 92 and 95). Discontinued one was 85 or 87 I think.

---spark plugs were right and also look good in the other stages BUT I still have that kind of banging in low gear.
I could tight more the carburetor nuts due to possible air leak...but I do not know.

I did not had this banging with the previous 626 but did not idle; this one does not idle too. The bike only idles when hot; so if I touch a bit the screw after a short ride the idle is too fast.

Thanks
It's not supposed to idle when cold.

What kind of banging in low gear?
Posted By: reverb Re: carburetor, phases, road tuning - 12/18/17 4:19 pm
...yes, but shut off too.
Intermittent banging.
Loud banging in the exhaust while slowing down with the throttle shut is usually caused by an air leak where the exhaust pipe fits onto the cylinder head.

Weak mixture at small throttle openings can cause a less-loud banging or popping in the exhaust. The cause can be an air leak into the inlet manifold. Test by spraying WD40 or similar on the joints while the engine is idling. Other causes can be maladjusted idle mixture screw or a too-big throttle slide cutaway.
Posted By: koan58 Re: carburetor, phases, road tuning - 12/18/17 6:44 pm
If its on closed throttle engine braking, likely TT's suggestion of an exhaust air leak, possibly combined with a (partly) blocked idle jet. Does it happen just on one side? May give a clue.
Posted By: John Healy Re: carburetor, phases, road tuning - 12/18/17 7:23 pm
Quote
If its on closed throttle engine braking, likely TT's suggestion of an exhaust air leak, possibly combined with a (partly) blocked idle jet. Does it happen just on one side? May give a clue.


Agreed, plus a too weak pilot air mixture (pilot air screw screwed out past 1 1/2 turns to compensate for a too rich slide cutaway).
Posted By: reverb Re: carburetor, phases, road tuning - 12/18/17 8:20 pm
...the cutaway is the one that comes with the carburetor, so is a #3. As mentioned, the plugs are right at all the phases; if the cutaway is not the correct the plugs would have another coloration.

-when slowing down is all ok, the intermittent popping is only in 1 and second gear.
No air leak in the manifold; no goo or blocked idle jet; not one side because is a 500 pre unit so one carburetor.

-If the mixture is too weak how the plugs look right?

Engine noises are not directly related to what gear you are in. The engine doesn't know what gear it's in. Is the gearbox banging?


Tell us what throttle opening the noise occurs at. Tell is what rpm.
Posted By: reverb Re: carburetor, phases, road tuning - 12/19/17 1:23 am
...do not see how I can go in top gear with the throttle almost open or the other way around...hence that I mentioned that the fact occurs in low rpms so low gears...anyway;
I do not have tachometer but around 1500-1800 rpm s.
Around 1/8 open throttle, so like Mr Healy is saying could be a weak mixture, but the screw is in the 1 1/2 turn.
-I do not have an erratic slow running.
Posted By: Stein Roger Re: carburetor, phases, road tuning - 12/19/17 9:13 am
I believe it would be happier with a 3.5 slide.
Posted By: Transgarp Re: carburetor, phases, road tuning - 12/19/17 2:11 pm
I use A/F Ratio Innovate MTX-L plus for tuning
http://www.innovatemotorsports.com/products/mtxl_plus.php

http://transgarp.dyndns.org/motorcycle/2000/20170914/16.JPG
http://transgarp.dyndns.org/motorcycle/2000/20170914/17.JPG
Posted By: Stein Roger Re: carburetor, phases, road tuning - 12/19/17 5:09 pm
You're clearly not into old bikes for their simplicity. laughing
No offence!
Posted By: reverb Re: carburetor, phases, road tuning - 12/20/17 5:00 pm
...with a 3.5 will have a leaner stage; do not want that.
Posted By: btour Re: carburetor, phases, road tuning - 12/20/17 6:14 pm
reverb,

I think what is being pointed out is that if your slide is too rich, you compensate by making the idle air too lean. It seems your problem is occurring on the overlap of these "two carbs" within a carb. Also your cutaway may be stamped with a number, but that number is just an estimate of the actual cutaway. You could try the 3.5, and you can emory paper your 3's to 3.25. IOW's you can fine tune the thing.
Posted By: reverb Re: carburetor, phases, road tuning - 12/20/17 10:33 pm
...I do not compensate the screw; as mentioned, idle screw is at exactly 1 1/2 turn and the plugs are right.
I do not have hesitation, no erratic running.
Posted By: koan58 Re: carburetor, phases, road tuning - 12/20/17 11:39 pm
I'm doubtful that you have a problem, unless it is in the gearbox?
Posted By: desco Re: carburetor, phases, road tuning - 12/21/17 12:31 am
Exactly 1 1/2 turns is a starting point. It may be correct or it may be 1/8 or so of a turn one way or the other to be correct. That's where the fun comes in on these old turds. No two carbs are the same. No two cylinders run the same. Experiment, experiment, experiment.
Posted By: reverb Re: carburetor, phases, road tuning - 12/22/17 3:52 pm
...besides your sarcasm Koan58, with that popping banging I was worried to have a possible lean situation. If I have free time today I will check again.
Posted By: koan58 Re: carburetor, phases, road tuning - 12/22/17 5:37 pm
No sarcasm there at all Reverb. You've said you are confident that the mixture/plugs are good at all ranges
The weird thing is that this "banging" only occurs in gears 1 & 2.
In general, carb tuning faults are not gear or rev specific, they are throttle position specific. That is why I questioned the gearbox, as someone else already has.

So my difficulty is to come to a theory as to why this happens only in gears 1 & 2.
Could it be that only in those gears are you able to trickle along on the tiniest whisker of throttle at very low revs?

If so, then it points to something that causes an occasional misfire at those conditions. This could be:-

- weak or mistimed spark at very low revs. I know nothing about Hunt magnetos, so I won't even explore this.

- wrong (probably weak) mixture at very low throttle openings. I think this the most likely. It would be at such slight throttle that the mixture is strongly governed by the pilot jet circuit. A weak mixture here could be a partly blocked jet (or the tiny pilot holes) or too much wear clearance between slide/body.
Alternatively, an over-rich mixture here could be caused by an enlarged pilot jet, due to clumsy unblocking.

There seems to be some doubt about the bike's ability to idle. I think this is the best area to investigate.

With the engine fully warmed up, can you obtain a steady, relaible, fairly low idle? Take special care that the setting of the air screw gives the highest speed, ie that turning it half a turn in or out will lower the speed.
If you can get a nice idle, how many turns out from fully in is the air screw? By turn, I mean 360 degrees. If you get this nice idle, go for a test ride.

If you can't get a low, steady idle, or if the air screw is far away from 1.5 turns out (anywhere roughly between 1 & 2 turns would be ok), then the pilot mixture needs further investigation.
Posted By: btour Re: carburetor, phases, road tuning - 12/22/17 6:41 pm
As mentioned, The pilot could be, and most likely is partly clogged, unless you have cleaned it lately with #78 drill bit. Get one, try it. It is a treat what a difference it can make.

I was afraid at first of breaking it off inside and not being able to retrieve it. But even though my hands are not the steadiest, it is easily done if you take your time and be patient. I practiced first on an old swap meet carb. That gave me confidence. You can do it with the carb still mounted on the bike. Just get a seat to sit on. Offer the bit to the jet (firstly set the bit in a tube of some sort) sort of poke around until you have found the entry orifice. This can be the hardest part. Once I find it, I very gently push it in until I feel it bottom, and gently twirl it bit as you withdraw. Check the bit. You will most likely see some black, or maybe grey/white if you use leaded, (which came out of the old carb), that provides more resistance than the black, which you can hardly feel.

At the end celebrate, you have just resized the carb, and done the fastest Big tune up possible, with a tiny tool.
Posted By: John Healy Re: carburetor, phases, road tuning - 12/22/17 6:49 pm
When you say banging, just where intake side - exhaust side or when is it banging, on acceleration, steady throttle, deceleration?
Posted By: reverb Re: carburetor, phases, road tuning - 12/23/17 5:38 am
...hi Koan58, see with other point of view, without thinking in the gears but think in going slow (hence low gears, hod do you go slow in top gear?)
I did not said that the mixture is good in all the phases, only said that the plugs look right in all the phases (hence...)

Looks more carb problem than a misfire.

Regarding idle, yes, only idle when hot but if I put lot of kms at top speed, the idle is too high (more than 1000 rpms)
If I move the throttle screw, normalize but then will be too low when engine be less hot or cold shutting off always.

Hello Btour, I bought a non premier carb but somehow this body is a premier carb (may be all the new 626 are like these?) so have the other screw in the opposite side and the conduct is clean; also I passed a guitar string.

Hello Mr Healy, as mentioned is an intermittent popping at around 1500 rpms or so with a "fixed" throttle near 1/8 open. No popping sound on deceleration at any stage.
All carb parts in good conditions; open exhaust pipes and air filter. in 20 years may be this is the first time doing this but I am not totally sure but always with the same set up except for this new carb bought a year ago or like that.

Posted By: gavin eisler Re: carburetor, phases, road tuning - 12/23/17 12:08 pm
Try screwing each pilot air screw in one 1/4 turn then report back on symptoms.

1.5 turns out is a general starting point, in your case this seems like it might be too weak.

The fully warmed up setting is the correct one, ( max idle speed from pilot air screw settings , erring a little to the rich end of the screw setting) if the bike struggles when less than fully warmed consider fitting choke slides.
Posted By: reverb Re: carburetor, phases, road tuning - 12/23/17 3:15 pm
...I will try.
Yes, I was thinking to put a choke.
Posted By: koan58 Re: carburetor, phases, road tuning - 12/23/17 3:45 pm
Hi Reverb,
I speculated that the problem only showed in gears 1 & 2, because only in those gears could you trickle along on the tiniest throttle. I find on my 650 I can do this on a level road, in 4th gear, at ~25 mph (which is ~1500 rpm), with just the slightest opening of throttle when the speed drops to ~20 mph. (dugga dugga dugga)
This most certainly isn't using anything like 1/8 throttle, more like 1/64. 1/8 throttle would be an easy 40+ mph on a level road.
So why can't you do 1/8 throttle in gears 3 & 4 on a level road, and get the banging then?
When the banging happens in 1st gear, at low revs and small throttle, can you feel the jerkiness of the bike? In which case it is a misfire.
Or is it still smooth while making the banging? In which case I can only imagine unburnt fuel is getting into the hot exhaust?
Is the banging worse when the engine is cold or hot?

Exactly what engine are we dealing with? A 5T or T100, what year? I guess an iron head with the "L" plugs.

Reverb, where is south cone? I'm guessing it's a warm part of the world? If so, why do you need hotter plugs? It is possible that you are hiding over-rich mixture fouling?

On the carb - wouldn't the original be 15/16" bore (~24mm)? Having replaced it with 626 (26mm bore), it will tend to run slightly leaner (lower venturi speed). I wouldn't expect this to be critical, but others may know better? Certainly make sure the gasket carb/flange doesn't intrude.

No sarcasm! Dave
Posted By: koan58 Re: carburetor, phases, road tuning - 12/23/17 3:47 pm
Ah yes! I meant to say that if you have no choke fitted, make sure the choke cable hole is blocked.
Posted By: reverb Re: carburetor, phases, road tuning - 12/23/17 10:41 pm
...hi Koan58, is a 48 5T. In the past I had the original carb but the 624, for example is a no no for the 500s pre or unit; the 626 is the way to go if you are a rider.
Man, South is South so no warm weather here, is somewhat similar to UK.
87 is not hotter is colder in Champion

No jerkiness, runs smooth with the banging associated. Is near night time here but I will take the road and see what happens.
Posted By: gavin eisler Re: carburetor, phases, road tuning - 12/23/17 11:05 pm
Ah, single carb , sorry, didnt click.
Extended throttle stop screw is a good idea for a single carb, screw in a tad for cold then back off when hot, easy to make if you have access to a lathe . Also available somewhere out there, google would find them. With no choke , pilot air mix usually ends up a bit of a compromise, once the tickle runs out they will run poorly when cold on a correct hot setting.
Posted By: koan58 Re: carburetor, phases, road tuning - 12/23/17 11:49 pm
Well Reverb, if it runs smooth while banging, it sounds like something going on harmlessly in the open exhaust pipe, I wouldn't worry about it.
Usually with Champions, the higher the number the hotter the plug, but what do I know?
Again, where is south cone mate? Dave
Posted By: reverb Re: carburetor, phases, road tuning - 12/28/17 11:46 pm
...hi Gavin, as you suggested couple hours ago I took the road with the screw on between 1/8 to 1/4 and the engine is banging far more now, also banging when deceleration at low rpms.
Posted By: koan58 Re: carburetor, phases, road tuning - 12/29/17 12:00 am
Reverb,
Its impossible to know what you mean by "the screw on between 1/8 to 1/4".
Is that throttle opening?
If so, what have you changed to make it bang more?
The air screw should be at least 1 full turn out from bottom. Dave
Posted By: reverb Re: carburetor, phases, road tuning - 12/29/17 1:36 am
...hi Koan58, as Gavin suggested I turned in the air screw that amount, I had it at 1 1/2 turn. I will try a bit more tomorrow if I have time.
Posted By: koan58 Re: carburetor, phases, road tuning - 12/29/17 2:25 am
Ok rev, the air screw is meant to be an idle adjustment.
Say the best setting for tickover is 1.5 turns out, when engine is hot.
Quite often it may be found that turning it in by 1/4, to 1/2 turn, that it makes an improvement in the low throttle region.
This is trial and error.
So if your last change made it bang more, go a little the other way.
Posted By: desco Re: carburetor, phases, road tuning - 12/29/17 3:39 am
Those idle air screw adjustments can and should be made while on the road, Carry a small screwdriver and when the motor is heated up make SMALL adjustments in and out beside the road. 1/8 or less is minor. 1/4 turn more or less could mean other problems. Don't even shut the motor off. Make an adjustment and keep going. Banging has no meaning. Backfiring is small explosions in the exhaust, like gun fire.
Remember, trying to fix one of these old turds on the internet, particularly with a language barrier, is like a doctor trying to diagnose cancer over the phone.
Posted By: gavin eisler Re: carburetor, phases, road tuning - 12/29/17 11:46 am
If making the pilot mix richer creates more banging, are you certain there is no leak at the header joints, either pipe to head or pipe to silencer, any leak at all will cause popping in the pipe on the over run.
Posted By: John Healy Re: carburetor, phases, road tuning - 12/29/17 4:09 pm
Let's understand why you get banging in the exhaust in the first place and then look at what is being said. Banging in the exhaust: There are three things you need for an air fuel mixture to have combustion: Air, fuel and heat. Under normal conditions you will have only two available in the exhaust (pipe/muffler) - fuel and heat. You will be missing air!

There are three ways you can get air into the exhaust system: One is an exhaust pipe air leak. The second is a very lean pilot air mixture and the last is an intake air leak (you have very high intake manifold vacuum on the over run which can momentarily open an air leak not present under normal driving). Any one, or a combination of two or more, can cause combustion in the exhaust system and the bang you hear on the over run.
Quote
Hello Mr Healy, as mentioned is an intermittent popping at around 1500 rpms or so with a "fixed" throttle near 1/8 open. No popping sound on deceleration at any stage.


So why are we talking about banging (now popping) as if it was related to a lean mixture?

So to a previous question: is it popping on the intake side or exhaust?
Posted By: Hillbilly bike Re: carburetor, phases, road tuning - 12/29/17 6:07 pm
Quote
Hello Mr Healy, as mentioned is an intermittent popping at around 1500 rpms or so with a "fixed" throttle near 1/8 open. No popping sound on deceleration at any stage
If not a lean mixture random misfire caused by carburetor issues.... a leaking intake valve can cause this.....
Posted By: reverb Re: carburetor, phases, road tuning - 12/29/17 6:22 pm
...I bought this carburetor due to I did not obtained a right idle with previous one. The same day I removed it from the bike I sell it to a guy with a Sunbeam 500cc that never ever idle or started first kick with an smaller Amal that had; instantly the Sunbeam started first kick and idle with a cold engine and without choke...so figure out.

-I am looking like a newbie but this engine (or the fuel, carb) seems like to change every few months or years hence this new problem.

As mentioned I have the thick O ring and a gap of .048 between carb and manifold. Do not have an air leak between the manifold and the head. The pipes do not have holes and are open as mentioned too.
The popping sound (now increased as write in the previous comment) is mainly out of the left exhaust pipe.

I can record it but I cannot post it.

---about that leaking valve could be due to may be some of you remember a thread were I had trouble with a contaminated gasoline. I cleaned the head, manifold and carb but did not removed the head.
Posted By: quinten Re: carburetor, phases, road tuning - 12/29/17 7:40 pm

Exhaust valve problem on the banging side
?
Posted By: John Healy Re: carburetor, phases, road tuning - 12/29/17 9:58 pm
Quote
I bought this carburetor due to I did not obtained a right idle with previous one. The same day I removed it from the bike I sell it to a guy with a Sunbeam 500cc that never ever idle or started first kick with an smaller AMAL that had; instantly the Sunbeam started first kick and idle with a cold engine and without choke...so figure out.


Back to basics - for the last time (where have I herd that before?) A cold engine will not idle without a very rich mixture!!!!!!!!!!! I can hear the deluge now! "My, bike runs great and it idles when its cold". Imagine how much better it would run if it wasn't stinking rich!

It is the reason we tickle the carb and/or turn on the choke.

The bulk of gasoline is made up of compounds that will only evaporate when exposed to internal engine parts (valves, dome of piston) that are at least 400° F, or hotter. A small portion of the fuel contains compounds that will evaporate at temperatures around 180° to 350° F. A very, very small portion of the fuel will evaporate at temperatures hovering around 125°F (vary with time of year). There are so few of them that it takes a lot of fuel to garner the energy to get things rolling.

If you bike starts cold, and idles without a choke, it HAS TO BE RICH on the idle circuit... period. You can do it. That is idle while cold, but it can only do that if the idle fuel mixture is rich.

Google volatility gasoline and 10%, 50% 90%
Typical volatility at 10% 50% and 90%
Posted By: desco Re: carburetor, phases, road tuning - 12/30/17 12:01 am
Mr Healy,
You have been preaching that sermon for so long I finally listened to it. My 72 does not have a choke so it kind of spits and sputters for a mile or so then it goes like rocket.
The 68 has choke but I still have to take it easy for a bit and then it to takes off. Did them both last year. Should have done them eons ago.
Thanks.
Posted By: htown Re: carburetor, phases, road tuning - 12/30/17 12:31 am
Another way to end up with an over rich bike is to jet to get a chocolate brown plug insulator. With today's ethanol laced, no-lead gas a properly tuned bike is going to have a off white to very light grey to tan insulator.
Posted By: Hillbilly bike Re: carburetor, phases, road tuning - 12/30/17 1:27 am
Originally Posted by htown
Another way to end up with an over rich bike is to jet to get a chocolate brown plug insulator. With today's ethanol laced, no-lead gas a properly tuned bike is going to have a off white to very light grey to tan insulator

That's also true with leaded racing fuel...and non ethanol fuel from what I see...
Posted By: reverb Re: carburetor, phases, road tuning - 12/30/17 1:44 am
...Mr Healy, I think that you misread that quote. Is a comment about the old carb and a Sunbeam, not my Triumph.
Anyway, I never said that the bike idles when cold. The carb is not rich.

Hi Quinten, not sure because I did not removed anything yet; but now is my only mechanical transport so I do not want to dismantle too much.
Posted By: htown Re: carburetor, phases, road tuning - 12/30/17 3:46 am
Along with the chocolate plug another way to end up with an over-rich bike is to freak out about blued pipes. If you are not getting a straw to blue discoloration through the first pipe bend you are not running at optimal efficiency. Certainly with repop pipes, which seem to discolor easily.
Posted By: John Healy Re: carburetor, phases, road tuning - 12/30/17 4:28 pm
No I read it right. My comment is about your comment that the Sunbeam."instantly the Sunbeam started first kick and idle with a cold engine and without choke". Your words, not mine.

For a cold engine to start, idle and run any where near smoothly immediately it has to be rich. You either have to put on the choke or the fuel mixture itself is already rich.

Remember for gasoline to burn it must vaporize. That is it must change from a liquid into a gas. The bulk of the compounds in fuel will not vaporize until the liquid is over some 300°F. When the engine is cold they pass through the engine in the same state they left the carburetor - as a liquid in the form of droplets. If all we had in the fuel were these compounds, with a high boiling (vaporization) point, you would have to light a fire under the engine and let it heat up to some 300°F before the engine would start.

There are a small amount of other compounds that have a boiling (vaporization)point at some 180°F that help the engine through the warm up phase, but we are talking about here is the "light" (low vaporazation point) compounds that let the engine start in the first place. Their boiling point varies with the seasons. Their volatility varies with the ambient air temperature. To reach the required temperature for these light (aromatic) to vaporize you add the ambient air temperature to the temperature reached when you compress the air/fuel mixture. When you compress a gas it heats up so compression is important factor when trying to start a cold engine. There is not enough of these light compounds in the fuel, without flooding the engine with fuel, to create energy to start the engine. To get enough energy you need to provide a rich fuel mixture, thus the need for a choke.
Posted By: John Healy Re: carburetor, phases, road tuning - 12/30/17 4:29 pm
Quote
Another way to end up with an over rich bike is to jet to get a chocolate brown plug insulator. With today's ethanol laced, no-lead gas a properly tuned bike is going to have a off white to very light grey to tan insulator.


YES!
Posted By: Tigernuts Re: carburetor, phases, road tuning - 12/30/17 5:09 pm
Not intending to throw petrol on the fire, but I have just started both my bikes this afternoon, for the first time in months. I've been ill with serious joint problems since late September and haven;t been able to even think about getting my leg over their seats, let alone kick the buggers over, until now. I thought I may as well try, though with petrol bought nearly 4 months ago and the temperature in the shed 8 degrees (that's about 40 degrees F I think), I wasn't hopeful. But both fired within 2 or 3 kicks and kept going after another 2 or 3, with a bit of careful throttle coaxing until they'd warmed up a little. As soon as they were slightly warm they ran fine (wouldn't tick over of course but they picked up beautifully and sounded perfectly normal). Both have 930 carbs with pancake airfilters and no chokes. I can't remember what kind of petrol I put in them but most likely the superunleaded from down the road, which is a supermarket brand, nothing fancy.

I deliberately adjust my mixtures to be slightly on the rich side, in the hope this will help cooling and thus make piston crown damage less likely (having seen the results of weak mixtures on other people's pistons in the past few years). The downpipes have remained chrome-colour all the way up to the ports, but the engines run very cleanly with sharp acceleration throughout the throttle range, and fuel consumption is very good. The plugs run with near white insulators if I cut the engine on anything above about 1/3 throttle. If I check them after pottering through 4 miles of 30mph speed limit on the way home, they come out a pale tan. So I don;t think you need a ridiculously rich mixture to keep your pipes from bluing, just a sensibly rich one?
Posted By: reverb Re: carburetor, phases, road tuning - 12/30/17 6:02 pm
...Htown, my plugs are like what you described in all the phases.
I think that today by night I would go to a buddy s houses in another town, so I ll try again with the air screw. There are 60kms of road.
Posted By: Dibnah Re: carburetor, phases, road tuning - 12/31/17 9:18 am
What happens if you coast in gear with the ignition switched off? Does the popping stop?
Posted By: triton thrasher Re: carburetor, phases, road tuning - 12/31/17 12:42 pm
Originally Posted by Dibnah
What happens if you coast in gear with the ignition switched off? Does the popping stop?



If not, it must be the rider not the bike.
Posted By: reverb Re: carburetor, phases, road tuning - 01/09/18 6:42 am
...so after these days I put some 150kms more; checked the valves clearances, checked for goo on the pilot jet.
The left plug, where the pop pop sound occurs is a bit more leaner than the other.
Tomorrow I ll put 300kms more and the weather will be warm...I am thinking to change the needle position; yes will be affected the the plug that is right but may be as a measure to avoid piston hole?
Or do not?

Posted By: Tigernuts Re: carburetor, phases, road tuning - 01/09/18 6:31 pm
Better to have one cylinder right and the other too rich, than one right and the other weak
Posted By: reverb Re: carburetor, phases, road tuning - 01/10/18 10:34 pm
...I decided to not change the position to this trip and see what s going on. The last 30kms I did it at 3/4 throttle all the way. The plugs have the same color now...
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