Getting the Tazland BBK, GEARS, + MLM ran on a dyno

[Meatball]

WOW, clark. All this info is great! Keep it rollin, man! I cant wait till the perfect combo is achieved and the Spree runs 40+mph reliably. Thatd be sweet!

[jakubman1]

So did this thing run lean or what?? Did it seize yet? I seized mine even running the 100 jet.

[eclark5483]

It ran very lean initially with the airbox lid and filter in place. Afterwards it did not run as lean, but the spark plug would to foul. Best guess is that it was being saturated with too much oil. Too much oil can cause a lean condition. It is (was) being ran with the oil pump attached, and a 64:1 ratio in the tank. The pump has been alleged to pump out 70:1, others have said it produces 50:1. Going by the assumption that it is producing 70:1, and adding in the 64:1 in the tank, the actual oil ratio that was used, was probably around 33-34:1, which, again, appears to be too high of a ratio at this point. If the pump is actually delivering 50:1, then our ratio, at a guess is probably around 28-30:1, maybe even 26-27:1 ???. No the engine, as far as we can tell, did not seize, although something did cause some smoking to occur around the engine area in test 2. In all 3 tests afterwards, it was ran WOT and did not hiccup, but would die out when throttle was released. This we can assume, is attributed to it being ran without the air box cover in place and air filter removed. Once the lid and filter were put back in, it idled fantastic, and started right up with a short press of the starter button. It did start to get a bit hot for tests 4 and 5 and the blowers were turned on to help cool it down. Tests 4 and 5 were ran with no lid, no filter. Today's Dyno run was just a test of basic conditions with no pressure adjustments to the air box, and no pod filter readings.

Here is what's interesting. When the filter is on the bike and opened up WOT with no lid, it produces some awesome horsepower with a lower RPM. If no filter is applied, it can still rev probably past 10,000 RPM, but horsepower and torque drop significantly.

You'll notice in video 2, it hits 35mph at a mere 4300 (8300 actual) rpm. Without the MLM the max RPM would at a guess be around 7500-8000 rpm?? Meaning the bike SHOULD be able to hit 40mph+ in that range with just the BBK and gears.

But anyways, since we see it drop HP+Torque with open air, we know that the bike, at that point, is probably starving for fuel, which will of course, make us lean. What we can conclude at this point is that a back pressure is needed on that air intake to help deliver fuel. In test 5, the filter was gone still, but a small back pressure was applied on the air box. The bike was then able to get the needed fuel, but the plug fouled. And again... too much oil saturating a piston can ALSO cause a lean condition.

My theory at this point, is that the BBK should (possibly) be good with just a mere 50:1 or maybe 60:1, or even 70:1 oil/fuel ratio. 33:1 as it is running now, is saturating it. On next weeks run, we are going to try again with the pump providing the oil and the tank filled with 100% gas with no premix. We will also be applying different pressure levels to the air box. The brand new Honda OEM filter will be put in place and the cover will have strong tape applied over it and holes drilled in various sizes till we find a back pressure the bike likes. If there is time (I have to work that day as well), then we'll even try the UNI pod filter to see what kind of readings it gives.

[MrJumps]

1. If you making more power without the lid and fikter your going lean, lean burst make s*** tons of power and if you were dieing after letting off the throttle your probably soft seizing.

2. Tempature dosnt matter on the dyno as much as a/f ratios going into the cylinder. Its getting cooling via the blower so its like water cooling. You can seize a water cooled motor when its well below what a regular road ran air bike will seize at.

3. The mlm is a general tuned pipe it may make a high rev Nd get more ho at the loss of tourqe.


I may be wrong on all 3 of these things and if I am I am sorry but to me if your gaining power when removing restrictions thats more air, your going lean and your probably soft seizing.

Also people that delete the pump say they get some decent rev difrence out of their bike. I woukd belive it the bike barley makes any power to begin with. That may be another test you may want to run.

[eclark5483]

No, we LOST power when removing restrictions. Compare videos 2 and 4. In video 2 the air filter (no lid) was still there and that's where horsepower peaked. in video 4, it was running free air with no filter, you'll notice that to achieve even 35, it had to be pushed to around 8800rpm, whereas, in video 2, it hit 35 at a mere 4300 rpm, THE SETTING WAS OFF ON THE DYNO IT WAS MORE THEN LIKELY 8600 RPM YOU WERE SEEING, but it made it's best horsepower run in video 2.. But yeah, any input you or anybody else can give before next weeks run would be helpful. Thank you.

Edit: In video 1, it ran REAL REAL bad. This was to be expected. It had the filter and lid in place and was sealed up tight. At that point it wasn't getting enough air obviously. Made TONS of smoke, filled up the Dyno room with it, had to open the back door to let some fresh air in.

[MrJumps]

Wait what now, can you post your findings as a excell chart? I am dyslexic and having extreme issues trying to understand your findings. Would be greatly appreciated

[eclark5483]

I'll get on that later if I remember, but recap:

Video 1: FILTER AND LID IN PLACE, NO HOLES DRILLED YET

Videos 2 and 3: Lid removed, filter still in place, 35mph @ 4300RPM?? More like 35mph @ 8600

Videos 4 and 5: Lid and filter both removed, run free air. 35mph @ 8800RPM

[eclark5483]

What's very obvious here, is that we do indeed need the lid and we do indeed need to drill holes in it. Next week is determining what hole size and how many. Also need to recalculate oil. If pump is producing 50:1 and 64:1 is in the tank, that's a super high amount of oil being pumped in. If the pump was doing like say 64:1 and the tank had 64:1, that right there would be 32:1 when combined. It's kind of a blind mystery at this point at how much that pump is actually putting out. Either way, it's saturating the plug out as it is now. This was determined in video 5. When it was ran free air, we could still see an excessive amount of oil getting onto the sensor rod. This of course, should not have been happening in an ideal oil lubrication.

[Meatball]

I concur with Jumps. Lean makes it have power like its on sterroids!...right before it seizes. Sounds like youre definitely on the right track. Finding a balance of lid holes, oil delivery and main jet so it can run at wot in a safe temperature range. During the break-in period of my bbk attempts it ran beautiful at low-to-mid throttle. Take-offs from 0-20mph were smooth and it pulled like an animal. It stayed cool, never smoked and didn't get anywhere near dangerous temperatures. One bbk went 70mi this way before I tried wot and the other was over 100mi. Both times they heat spiked and soft seized when trying to go higher rpm's up to around 30mph. After changing my main jet 5 times and trying different holes in my airbox, I just gave up from frustration. I never even thought about too much oil delivery. My oil pump was deleted and I was running 32:1 in my tank the entire time.

[eclark5483]

Next weeks agenda, is where we will try holes in the air box. What we plan on doing is installing the brand new Honda OEM filter to replace the old dirty one, taping the airbox top off with some duct tape, poking about 4 or 5 pencil/pen sized holes holes to start with, then keep adding holes till we get to where we think it should be. Just keep increasing little by little till we are happy with the results. And of course, run it with 100% gas in the tank and just the pump. Other then that, I'm at a loss how to approach it if this theory fails.

If it DOES succeed. Then at a guess, those who want to run it without the oil pump, should be able to run it with whatever the pump normally puts out as a premix in their tank.

70:1, 64:1, 50:1??? Who knows at this point for sure, but it would be significantly less then the 32:1 that others HAVE BEEN trying up to this point. But then again, maybe I'll end up being completely wrong here as well and will end up having to swap out the engine for the one on the bench. Guess we will see..

[eclark5483]

So did this thing run lean or what??

Just a little science FYI jakubman1 so the video's make a little more sense to you and anybody else. LEAN/RICH conditions can, for the most part, be drawn at 14.7 AIR/FUEL ratio for your system stoich. 14.7 is usually referred to as the ideal burn for gas, getting a higher number then 14.7 means you are lean, getting a lower value means you are running rich, but that doesn't tell the whole story. Max power is made anywhere from 12.0 to say around 13.5 (Video evidence suggests the Spree is happy around 13.5). You want that bit of extra fuel in the engine so it has it available to burn. When dealing with a 2 stroke that has oil in the fuel, the dynamics change a bit. You won't be burning as much actual fuel as you could/should.

Edit: Reference what Taz was telling you here: viewtopic.php?f=1&t=33591&start=30#p291657

If you look at the first piston you fried it was dark and looked like it just overheated. The first piston looked well lubricated. If you look at the second piston it looked like it was super lean. The piston was white and the spark plug was white.

Also reference what Meatball had stated here: viewtopic.php?f=1&t=33591#p291510

My plugs always looked nice and brown. A few times they were wet and oily so I adjusted from there

So did it run lean? In video 1, yes it did. In videos 2-3 it was within the ideal stoich range for an efficient burn, and in video 4-5 it was running a bit on the rich side (HP+TORQUE LOSS, OPEN AIR WITH NO BACK PRESSURE). But again... what we experienced was plug fowling from excessive oil which counter-acted the rich condition and took it right back into lean. See what I am saying here? This is why I said we needed to recalculate oil delivery. Also, when back pressure from the airbox is applied with filter and a to be determined number of holes, the stoich returns to an ideal range for idle and WOT burning. There are reasons why stoich should actually be more in the 12's ideally, but no reason to get into those dynamics just yet because the actual stoich for a normal Spree has not yet been determined. Plus, lower stoich is typically done by the guys with 2 stroke racing bikes. Let's be honest here... this is a Spree, it is NOT a racing bike. While the BBK does take it from 49cc to 68cc, we can't honestly use racing type tunes and adjustments to get it to run a proper powerband. And again, I'm sacrificing the BBK in the name of figuring out what DOES work right. Try not to be negative, I know I'm hoping I (literally), don't blow it and can come up with the optimal conditions to run it under.

[eclark5483]

Also, for those looking at the videos and seeing that it ran lean in VIDEO 1 when the airbox lid and filter were in place and Shawn is saying "IT'S GETTING TOO MUCH AIR" and you're going... HUH?? WHY WOULD YOU ADD HOLES THEN?? To explain this, and to test this out yourself. Think of a vacuum cleaner. Where do you get the most optimal vacuum suction out of it? When the filter is clean, and it is sealed off of course. What can make you lose suction? Exposing it to open air. So when one drills holes in that airbox, what they are doing, is not letting more air in per say, they are reducing the atmospheric pressure. The fine balance one is looking to achieve, is still maintaining some air vacuum, but reducing how much is getting thrown at the fuel before it mixes in the venturi and sent to the piston for ignition.

Ain't science fun!!

[Meatball]

I really think eclark is onto something. Adding holes wont increase air volume since every other component down the line would need to be opened up as well. Carb, intake, reeds, etc...all it would do is reduce back pressure. Its not a forced induction system like a supercharger or turbo. The air suction is only created by the upstroke of the piston, which in turn opens the reeds and the motor takes a breath. Reeds close on the down stroke and exhaust has nowhere to go but out the exhaust port and then muffler.

Interesting to think how important that back pressure is.

Amazing how they ever got motors to run 100yrs ago when their tools were basically sticks and rocks.

[MrJumps]

I really think eclark is onto something. Adding holes wont increase air volume since every other component down the line would need to be opened up as well. Carb, intake, reeds, etc...all it would do is reduce back pressure. Its not a forced induction system like a supercharger or turbo. The air suction is only created by the upstroke of the piston, which in turn opens the reeds and the motor takes a breath. Reeds close on the down stroke and exhaust has nowhere to go but out the exhaust port and then muffler.

Interesting to think how important that back pressure is.

Amazing how they ever got motors to run 100yrs ago when their tools were basically sticks and rocks.

1.the stock intake actually is reduced by the airbox with the lid and filter in place. Thats why it wont run right with a pod filter, it needs the shut off suction of the airbox to open the reeds and pulse right.

2.Adding holes will add air flow not volume nessisarly, think of it as a mc donalds straw versus. coffee stirrers, your throat is the intake and the bike being your stomach. Yes your throat and stomach dont change size but your restricted on your sucking ability with a coffee stirrers. Now switch to the mc dolands straw (this is the holes you drill in the airbox),now you can breath better but your still restricted. Completely remove the straw and much like the spree you gulp in air and your throat gets sore just like the piston walls going hot from bejng lean.

OK, since my fuel ratio for the Dyno run has been figured out. I'll throw in this other stat. I just ordered 4 quarts of Pro Honda GN2 Injector Oil. Can't remember what was in there, I think it was the cheap stuff from Walmart I tossed in back when I first got the Spree and was trying to get it to run. Going to make sure the oil being used in Genuine Honda for the pump, will probably use the GN2 in the tank as well.

3. This section is pulled from your other post where you blew like 2 cylinders. I dont know if you know this but any premix or oil thats "....was the cheap stuff from walmart...," is gonna tear your motor up.

I dont think using the spree bbk is worth it. These kits burn up. Ive tried everything from drilling holes to putting a main jet 100 to moving the needle notches.
Im happy doing 35mph with my mlm pipe and thats IT !!
I spent 220$ just messing up my crank bearings while running to lean. Id like to see someone who actually had success and post a video about exactly what they did. its just fishy. Even Meatball BABY'd his and STILL burnt his up.
Just buy a bigger scooter if ya wanna go faster IMO

4.Honestly you have a right to your opinions on weather this kit is worth it or not. But when you have issues tuning the bike and burn theough 220$? American? And then wanna go back and try again you have a legit case. But, in your case you have went and had your bike dynoed, now I wasnt born yesterday. Dynos are not accurate per run and your saying you ran only 5(five) passes?
Out of each of these five passes you changed a variable without getting a good base on a machine that can range plus to minus a few figures, without posting the full band sheets except for in a video. I can't find what your doing to be creditable. Your saying things and having issue explaining these things without just restating what you already said. I honestly had no issues with the kit, you just have to take your time. Your obviously rushing through this changing variables and have a biased against the kit to begin with. More than 2 passes for sore more like five paases a variable.

Can't wait for the results. Do you want to try one of my bigger pilot jets for your dyno test?

Even though I send a main jet it is not a one size shoe fits all.

Taz

...My syringe didn't have any markings to adjust to 70:1, so I decided to just bump up the oil just a tad and went 64:1 in the tank....

5. Pull the oil pump and premix, there is no reason to try guess working with the pump your contorting your results to fail.

6. Slow down and document more, show us the charts, you can read a bikes power off the chart alot more that your descriptions, there too vauge.


And yes I spent a while writting this, if you wanna make claims that a bore/piston,bottkmend, etc part has issues and test on it you better document and test correctly. What your doing now is very sloppy and I see many areas where you have stated could of already ruined this bore your gonna run more passes on. You said your self your running lean on a dyno and the bike got "....hot...," how hot?


Here is my questions for you...

1. How did you break this bore in?
2. Have you leak down tested this bore and case from the intake?
3. If your tune correct and did you buy a proper tach and temp gauge and have been activly tuning based on that?
4. Why have you been assuming the oil deliver is the issue and changing it up so much?
5. Plug chops after each run?
6. Pulled the head after to look for scoring or if its predetinating?
7. What grade of fuel is being premixed along into the bike with the stock oil pump?
8. How hot is hot?


I am not trying to be a *, I just honestly feel this is rushed and messy as *. If I was to change variables I would pull head, measure for warpage and continue. Your just torchering the bore at this point.

[eclark5483]

Jumps, I think you are confusing me with jakubman1 and his problems..

Like when you said:

3. This section is pulled from your other post where you blew like 2 cylinders.

I have not blown any cylinders. The only heat issue turned out to be a tach pickup wire that was touching the MLM and started to get hot, and there was an issue that we discovered after a couple tests where the tire was rubbing on the kickstand (video 5), and created some heat.

As for the "cheap stuff" oil I was talking about, that was just some stuff I picked up to get it initially running with the old piston before the BBK was done. I drained the oil reservoir and added new lines. It is running HONDA GN2 INJECTOR OIL in the pump and in the premix.

As for deleting the pump, I have a very legitimate reason for NOT wanting to do that, and I have a legitimate reason for NOT running a premix in the tank.

Brent over on the 49cc scoot forums was talking to me about this as well. He suggested a 40:1 ratio might be a better choice and I agreed, but rather then repeat myself again as to why NOT, lemme just quote myself:

That will possibly be something I may look into doing later on down the line. For now though, I'm leaning more towards keeping the pump and zero premix in the tank for one key reason... The Spree is for my son with Autism. I would then be placing him in a situation where he would need to figure out how to do the premix every time he put gas in. A long term goal for my boy is to step him up to a bigger scooter, but at this point, he only wants to drive the Spree. Doing premix for him till he finally gets the courage to try a bigger bike is no big deal, but then I may be faced with a reality that he simply will not do that. In which case, what I ultimately might have to end up doing, is removing the BBK and taking the Spree back down to it's stock configuration.

But again, I can agree with 40:1 as the probable safe bet for the BBK. If the pump is in fact, putting out 50:1 like some have claimed, then it won't be too far away from a 40:1 ideal range, and with that, I'm guessing a good squirt of oil in the premix container should be good to go. I know I have seen some "claim" to get better revs when they delete the pump, while many other's argue that the pump is NOT bad at all and just gets a bad rep.

Pump .vs Premix gets ALOT of debate and alot of pros and cons from people who will swear by one or the other.

I think for the most part, Honda makes a d*** good bike and I have much faith in the pump. If it was a TaoTao 2 stroke with a pump though.... yeah, that pump would have been gone before even taking a first ride.

I just wish there was more data out there for these older scooters so calculating precise premix would be easier. But, one problem at a time is the way to take it. For now, I just need to get the BBK WOT stable and idling correctly.

Also, I don't have charts (yet), but I will get them. Shawn and I both had business to tend to and were kind of limited to what we could do for dyno runs so we chose to do just extremes.

*Lid and filter in place, no holes
*lid off, just filter
*no filter, no lid

I figured those 3 key run types would show what is happening with it at different levels... TOTALLY open to thoughts or suggestions before trying again.

The findings of too much oil, are based on the excessive amount saturating the probe in the muffler, and the plug acting as if it was fowling out. If you think this should be OK, then yeah, would love to hear any thoughts on that as well.

EDIT: And yes, I can agree with you that what I am ultimately doing at this point, is torturing that BBK, but then if you back up a bit and RE-READ where I quoted myself from the other forums, you would realize why I really don't care if I do happen to blow it up.

I've stated it from the very first time I ever posted on this forum... the scooters are for my special needs kids. I drive an Indian Scout. Scooters, even with a BBK are just too weak for me to want to play around on. If I blow it, I blow it... no biggy I'll just swap the engine and rebuild.. gotta have a hobby right??