2017 Beta 300RR Suzuki Needle questions.

[kcarsey]

Hello all, I've been doing some reading around using the NECJ needle in my 2017 300RR. Let me start with with my setup, then i'll talk about my symptoms and see if anyone else has seen this.

2017 300RR. Oil injection disconnected. Running Motul 800 mixed at 60:1 Pump 93 from name brand station, normally Sunoco. I'm anal about my gas and usually I pump 1 gallon of 93 into my truck, then pump 5 gallons into my can, to ensure I get 93 from the pump and not leftover from the hose. I'm very precise with oil measurements, and use a Ratio Rite to make sure I have the exact correct amount. Stock spark plug BPR7ES. 168mj 38 Pilot 1.5 - 1.75 out on air screw. NECJ 2nd clip around 600ft and 75F to 85F temps.

Once the bike is warmed up.. after say 15 minutes of mid to slow speed riding. 2nd-3rd gear single track, i'm getting some pinging on initial throttle opening. so say closed to ~1/8 opening. If I decel then slighly open throttle to maintain speed I hear pinging. If I open the throttle further to around 1/4 the pinging goes away even at 1/4 or further throttle opening at low rpm's, or really any rpm. I thought to myself, it must be too lean, so I moved to 3rd clip and same issues.

At this point I did some more reading, but did not see similar issues, so I thought it must be lean, so I ordered a NECW needle, put that in on 2nd clip, and it seemed to help slightly, but I still have pinging once the bike is good and warmed up.

At this point i'm truly baffled, so I put the stock N2ZW back in at 2nd clip. I have the blubbery bottom end back that I hated, and guess what, still some pinging, although not as much, and only when the bike is warmed up after some tight single track, using clutch in 2nd gear. Even if I hit some open trail 3rd 4th gear and cool off some, I still get pinging.

The strange part is, last year in august I went on a ride and got my bike hot enough to where it just started to spit a bit of water/steam, but not completely overheated and I never had a single issue with pinging, but the bike was also using the oil injection at that time. I'm also currently seeing higher idle once the bike is hot, which I never saw last year when riding the bike, even when "slightly" overheated. estimated 250F Never a single problem.

I'm starting to think maybe I have gotten some bad gas from my local station. I should also add that all of this behavior is on the same ~7 gallons of gas and all from the same station. Has ANYONE else had knock problems with the NECJ or even the NECW needle? I'm starting to think I might just need to find a different station, or ditch the crappy pump and move over to 50/50 mix of race fuel to keep the pinging away. I REALLY loved the NECJ needle but I was super worried I was too lean, considering the pinging.

Thoughts?

[aj_mariner]

Your assumptions are correct...ping, knock is a lean indicator, or plug running too hot.

This was the main reason I stayed with a 40pj last year...but the knock only happened on decel IIRC. The bike would also have the same knock when moving slow during warm up on the 40pj.
I switched to the BR7ES and didn’t notice the knock on warmup. Switched to ethanol free after a ride or two after the plug change.
On an 80degF day in early May at 1000-3000’...I switched to 38pj and NECJ clip 3. The knock came back on decel. Kept dicking with the air screw and took it down to 1-1/4 turns with no change.

Put in the 40pj with AS at 2 turns out and try again. I do not have a lot of riding time with the Suzuki needles above 80degF yet...but would give the NECJ a go at clip 3 with the 40pj...as well as suggest changing to the BR7ES. It doesn’t have the projected insulator, and will run a touch cooler.

Edit: what kind of riding do you do to change to a 60:1 on 800T? I would not mix any less than this. The 800T info sheet says 2% plus or minus 0.5% depending on how you ride the bike.

[kcarsey]

Thanks for the insight. I have a box of 4 BR7ES plugs in my tool box but as of right now I still have the stock plug in the bike at ~50 hours. I've pulled it a couple times and taken a look and it always looked good. I was afraid of fouling with the non-projected plug. I figured beta put that plug in for a reason, but i'll give the non-projected plug a try.

I have the beta owners/service manual downloaded and I believe they specify 60:1 which is around 1.6% Also quoted from 800 2T off road data sheet-

Mixing ratio : MOTO CROSS GRAND PRIX : 2% (50:1). In normal conditions decrease the percentage
by 0.5%.
Tune according to your own use.

Maybe i'll just move to 50:1 that way i'm sure i'll be covered under all conditions. If I ever do any high speed running or transfer sections on the road.

I don't have any knock on decel that i've noticed. If it's there it is very slight. I also considered switching to ethanol-free gasoline as I have some available locally that is 91 octane. Did you have good results with the rec fuel with no ethanol, but the lower 91 octane? In theory the ethanol adds knock resistance and should run cooler, but I question the consistency of pump gas. It seems they change the ethanol content all the time.

I have a 40PJ and i'll throw that in and try it out. I'm also getting an air screw adjuster knob that way I can get it tuned in perfectly once the bike is warmed up. I do know that the top of the needle diameter and also pilot jet size are related to each other, and it's not uncommon to have to richen/lean a pilot after making a drastic needle change. I guess i'll try the richer pilot and go from there. I had hoped that the NECW would have taken the knock away. I believe the only difference from the NECJ is that the W has a smaller diameter at the top which should let more fuel through at small throttle openings. All the W needle really gave me was not quite as smooth running because it was richer, and I still had knock.

[aj_mariner]

I felt the switch to BR7ES made the most difference eliminating knock on warmup. I’ve been running it for 40 hours with zero fouling issues or even a hint of fouling.

The best ethanol free gas close to me is mid-grade 90oct, but thought that switch was more for lubrication. Same results performance wise as 93pump gas with ethanol.

And yes, you’re correct about the difference between W and J. Pilot and air screw will affect idle jetting the most, more than the needle.

https://www.duncanracing.com/TechCenter/KeihinCarbJetting.pdf

I’ve been toying with the idea of changing my mix to 55:1 during summer to help keep the mix reasonable after some gas evap. But if you are running at 60:1 with similar symptoms as I did last year, maybe I’ll stick with 50:1

[kcarsey]

I’ve been toying with the idea of changing my mix to 55:1 during summer to help keep the mix reasonable after some gas evap. But if you are running at 60:1 with similar symptoms as I did last year, maybe I’ll stick with 50:1

All things equal, if I change from 60:1 to 50:1 my jetting will become leaner, that is, my engine will run leaner with the same jetting. The engine will be taking in more oil, and less fuel because the jetting will allow the same amount of premix to enter the engine. Since I have a higher ratio of oil to gasoline, there will be less fuel to go around since the same volume will be entering the engine because jet size did not change. It is a minor change, but a change towards lean regardless. It's not really fair to speak in terms of "leanness" and "richness" when talking about oil mix and it only seems to cause confusion.

What i'm really trying to say is, if you move from 50:1 to 55:1 and don't change anything else, your bike will run a bit richer, even though you have less lubricating oil.

Funny thing is i've never noticed knock on warm up, which in theory would be when the bike is running more lean, because cold engines require more fuel. I'm still thinking I've gotten some bad gas along the way. At any rate, i'll try the 40PJ with the NECJ and possibly the NECW and report back results.

Ethanol really does not have any affect on lubrication. It does have cooling effects similar to any other alcohol. In theory an engine will run cooler with more ethanol because it evaporates more readily, and also because approx 30% more ethanol it is required to achieve a stoichiometric ratio, compared to gasoline. It also has a higher equivalent octane rating compared to gasoline.

I think generally the biggest issue is consistency. On the pump it says "up to 10% ethanol". the reality is, it can be anywhere between 0 to 10% depending on what's mixed, and the season. The more Ethanol in the gas, the leaner your bike will run for given jetting. Ethanol also attracts moisture and attacks rubber parts. Boaters use it because straight gasoline will not readily mix with water like ethanol will, and it also works better in older machinery with real rubber and cork parts in the carb. In my experience ethanol free gas also lasts longer in storage and for that reason seems to work better in seasonal equipment.

Sorry for the mini rant, I just sometimes see a lot of confusion and mis-information out there regarding ethanol and like to set the record straight. I didn't site any resources, but if you look around a bit you should find the same information that i've shared here

[aj_mariner]

Agree 100% about mixing and confusion.

I’ve never looked deeply into it, but thought I remember hearing or seeing that ethanol will reduce or degrade premix. It was a suggestion that I followed without much hesitation since I’d rather be safe than sorry.

[Goatse]

AJ, be careful because you might be sending him down the wrong path. A few things jump out at me.

First, before we go anywhere. This,

Your assumptions are correct...ping, knock is a lean indicator, or plug running too hot.

is not always true on 2 strokes. What if the "ping" he is hearing is Pipe Bang? Pipe Bang is typically caused by a rich condition. Pipe Bang is fuel that made it out of the cylinder without being burned. It then gets lit in the pipe from the next exhaust pulse.

Which brings me to this,

The strange part is, last year in august I went on a ride and got my bike hot enough to where it just started to spit a bit of water/steam, but not completely overheated and I never had a single issue with pinging

When the bike is nice and hot you will have a more complete burn. No more fuel getting through the cylinder without being lit. Hence you not hearing it that day.


So back to AJ. This here is what brings us back to the pipe bang.

I felt the switch to BR7ES made the most difference eliminating knock on warmup.

Your hotter plug makes for a better burn before the engine gets nice and hot. So with the hotter plug you aren't letting some of that fuel out of the cylinder to just be lit up in your pipe (making the bang/knock).




So OP. A "ping" due to detonation (or pre-igntion) does sound fairly different than Pipe Bang. Pipe Bang is a pretty heavy knock and although generally harmless it does sound (and feel) much worse than actual engine knock. It's louder because it's going through the thin pipe and not the heavy alloy cylinder. The fact you mention them on decel leads me to believe it is more Pipe Bang that it is detonation. So if you find that it doesn't get better by throwing fuel at it, keep in mind that leaning it out might clean up what you've been chasing.

[Goatse]

Also, to note. I played around with the Suzuki needles a fair bit and I think a lot of people go down the wrong path with them. I was getting all these suggestions to go rich rich rich with the Suzuki needles. But every time I went with suggested jet sizing, my bike ran crazy rich.

So I actually took the NEDJ, NEDW, and the stock NOZJ (250RR) and just measured them myself. I measured them at 7 different points at the same difference from Clip 1, and measured them to the 0.001". The NEDJ was surprisingly very similar to the Beta NOZJ. Straight portion (idle) was bang on the same, but the taper just started a 'little' bit later on the NEDJ. But once that taper started they were pretty well bang nuts even right to the end. Then the NEDW was just as you'd expect. A smaller dia straight portion (richer idle), then the same (as the NEDJ) as it gets on to the taper.

So what this tells me. Since the taper starts later on the NEDJ vs the NOZJ this will be leaner (in that area) in comparison. But where people complain about the NOZJ 'is' right where you come on to the taper. So if guys are looking to clean up that area, then going with a bigger pilot is counter productive. Sure the NExx stays leaner longer, but that's the area that was too rich in the first place. So...

I went back to the stock jet sizes with the NEDJ and it was much better than all these suggested rich jets I was seeing on the internet. The stock jetting and the NEDJ (on a 250RR though) makes for a very clean running bike. That being said, I have went back to the NOZJ and it is because of the extra fuel on the bottom. I run an RK Tek head with 200 psi static compression and I like there to be a little bit of extra fuel in case I need it. Sure it can get blubbery at times, and I do get the tiniest amount of dribble out of the silencer, but I prefer it that way. Then you know you're getting enough lubrication.

[aj_mariner]

You may be right Goatse, but he said ping and knock in his first post, not pipe bang...and it sounds a LOT like what I was digging into last year. The only thing that fixed it was staying more rich on the low end.

[kcarsey]

Thanks for all the input everyone.

Just to clear some confusion up on the spark plug, stock on the 300RR is BPR7ES I believe Goatse is a bit confused. AJ said that he uses a BR7ES and I also said those are the spare plugs that I have, but have not tried. They are the same heat range, however the P has the protruding insulator, and the standard BR7ES does not. Also it's worth nothing that I don't have any high speed knock anywhere, or knock under heavy load, at least that I have noticed.

I really think in my case, from hearing all the opinions, i'm dealing with sub-par gasoline. With that being said, I would really like to use the NECJ or NECW needle for that smoothness. I did miss some of the hit off the bottom that the richer stock needle gives, but I guess that's the trade off. I might try both and just use which ever suits me best as long as I don't experience any knock.

I have never heard pipe bang, at least that I know of. I have worked on cars/engines/motorcycles for years and am certain of what engine knock sounds like. Also I'm not sure if I mentioned before, but it does not happen on decel at all, so I would reasonably assume it isn't pipe bang. Also I have a pretty keen ear for mechanical things. I had another guy ride the bike, and he didn't really notice the knock, when he got back, he said "sounds like chain slap to me"