Ignition Timing Explained & Tested : How-To Advance & Retard Timing With The MVT Digital Direct 

My career modifying two and four stroke engines has now spanned 51 years. I have modified everything from Formula One outboard tunnel boats to trials bike engines, drag racing, road racing, hill climbers, flat track, sleds, airplanes and ultra lights. I teach an internal combustion engine class on a volunteer basis once per week at a local Christian school for grades 7 through 12. I watch TONS of videos looking for those very few exceptional creations that I can recommend to my students, knowing that their information is accurate and useful for their “home work” and further study beyond what my time in the classroom with them can provide. I find nothing inaccurate or worthy of criticism in your EXCELLENT explanations! I am truly impressed with your precise, articulate and well conveyed materials. You are a RARE and very well versed gentleman, Sir! No arrogance, condescension or smart ass attitudes whatsoever. Just concise and real information. In my humble opinion, you are a learned GIFT to the industry and I sincerely salute you. Very well done! 19:51 Many deserved thanks!

to explain something so complex so well so that it is easy to understand takes a genius. thank you

Educational as allways! Here in Serbia (Europe), we have scooter forum since 2007 or 6... Our God is also Mr. A.G. Bell :)

This guy answered all my problems in mind, thank you sir..please share more of your ideas

Tqvm bro for the knowledge, I'm now more understand about ignition timing.. because I've made a up stroke to my motorcycle then I've a knocking problem..now i know what to adjust to my ignition timing..keep it up bro

You need to make a master class with your knowledge.

Tq sir for the knowledge..easy to understand..😊im your supporter sir..from malaysia🇲🇾🇲🇾🇲🇾✌🏻✌🏻✌🏻👍🏻👍🏻👍🏻

You're a genius.

there's a lot of self centered f^#K's that can't give a thumbs up or leave a comment that is very sad when seeing how many views you've gotten. Thank you for taking the time to make this video shared it with my son so he understands how to fix his racebikes.

5/5 stars mate now I know my timing too advanced! Can’t thank you enough!

Awesome. Completely useful & helpful. Sincerely yours.

A great job of explaining & the how & why to you moves 👍😊

4-stroke engine calibrator here, I have limited 2-stroke calibration optimization experience beyond the basics. Nice job researching and explaining the theories. I've been spoiled testing $150k prototype engines in $10m test facilities with all the dynamometer toys. I lust after cylinder pressure measurement setup, this is the future of home diy tuning, when OEMs start using cylinder pressure sensors on production cars, not sure when that will it's very costly to get accuracy and resolution today. On the bright side, you don't really need all that to maximize your fun, because we got folks like 49ccScoot to help us through.

Fantastic explanation and side notes

Très bonne idée ce test!! Merci super video! 👍

On lambretta we use a buzzwangle mercury switch attached to the flywheel, the digital read gives you degrees on the flywheel.

Plus one subs here. Salute

Can you please do a similar video for a diesel engine

And just like that.... All the kids go out and advance their timing 4deg 😂 Seriously though, good video. I really wish there were more maps available for review on the AM6. MVT makes the millennium with two keys for switching to digital which that unit has 3 curves with +/- 3deg adjustment on each with just a flip of a switch. The TPR kit has an offset key but it is not supposed to be used with the TOP red CDI. No details on the curve it provides Again, I would like to see some Dyno graphs on this 86 using different curves as to see where exactly this motor needs to be to have it singing.

Very very informative video... Thanks a lot.

You have made a fantastic clarification. I need a clarification: at what level does the BTDC spark plug start firing, and when does the spark end at what level (BTDC or ATDC)?

Man, you need a dyno 😁😉🏁🏁

i have put on a 100cc kit and since can get it to run right. seems it wants to run leaner than before . even the stock pilot jet(28) seems too much to idle. thanks for all the vids if it werent for you id be lost.

The formulas section of this video remind me of the video on finding your actual compression ratio. If you get into the timing in the future- make a piece on the mini lathe so you can adjust the timing via an Allen screw set at a right angle to the crank shaft. If you put a lock nut on the Allen screw and chart the degrees per turn of the screw you may be able to make very delicate but accurate adjustments of the timing advance.

Hello, I installed the MVT with the RJ34-6 CDI on a Honda DIo (41.5 mm stroke) at 0.35mm BTDC. I then watched your video and Pitobread video and I found out the curve you measured. I wish I watched before because 40° degrees advance till 8k rpm overheated my Cylinder and almost melted the exhaust and ruined the cylinder. I watched Pitobread suggesting to keep 28° at around 3k rpm. I was wondering what happens to the curve If I set 28° advance at 6k rpm ( Peak advance for MVT Curve) at 12/13k rpm or in general how the new curve is modified? Consdirering I drop by 14 ° the peak will the new curve be the same with 14° less at each step? I hope my question is clear. Thanks a lot in advance from Italy!

Well done

Many thanks for brilliant explanations!

hi sir! great video. just want to ask whats the best timing for my engine i have pushrod modified engine 72mm bore 56.4 stroke my mechanic told me that he retarded the timing a little bit. now i can feel the engines power when it hits 6k rpm above 5k below feels like just stock engine which is 67mm bore 56.4 stroke. dont now if it has anything to do with timing. id be very glad if you answer my question. thank you so much and keep up the good videos

Great video. can I set my ignition using just a graduated disc? thank you

Thank you

BRAVO MASTER

Thank you for your time great video. I am having issue with a yamaha rd 350 not going past 6k rpm supposed to 2mm btdc may have been off a bit lining up rotor notch to pickup edge no key in fly wheel.thinking i may be advanced and sounds like hear rattling in cylinders

I've got a Chinese 2stroke scooter can I do a similar thing with the timing like you did with project taotao? I'm trying to do a lower rpm build for something a bit different than the usual 14k rpm builds

Geesh!

Hey , I really appreciate your work . Could u help me out with measurement from the cable of ur digital direct ? What is the idle voltage of each cable from the ignition system ? White ? Yellow ? And what is the voltage of the regulator coming out on the red cable to the battery ?

How do you advance the trigger pickup to advance timing?

Wat size carburetor and jetting you are using on your scooter.

I have a 1980 yamaha DT125 that had a bad CDI box, I wired up a Chinese cdi box 6 pin connector with 5 wires, i get bad spark knock or detination on deceleration and inbetween shifts. Is there another CDI Box I could buy that would help? I assume it's because I have a 4T Cdi on a 2T bike

ZATEN DİSTRİBÜTÖRDE VKUMLU AVANS VAR DEĞİŞİK HIZLAR İÇİN AMA DAHA NAZİK DAHA İNCE AYARLI Bİ SİSTEM OLSA İYİ OLUR.

Hello, I have a cbr 150 big bored 171 with pe28 carb and an ignitech, I would like to know if there is any upgrade map or how many degrees would I set as max for safety (rev limit 11800)before I blow my engine, it is for circuit use, thanks

It had been better in 150km\h.I ordred new original motor Peugeot V-Clic gy6 139qmb,for 700 with shipping+tax,530 wich is cheap.New scooter cost 900,so I could get much spare-parts,but didnt.So I have 3,one un-original for 300.Planned to buy original exhaust with egr-connection.To get away high compression sound for bigger cylinder.60cc has begun to rumble in start,and making groove noise,so needs to be aggresivle tuned back both needle and screw.

I have a Minarelli 70cc with a crankhsaft 39.2 stroke , with what value can i set my MVT?

How do you get your 0-30, 0-40 and 0-50 times. Do you have a gps app that does that?

Ignites TDC or ignites BTDC. Which one is better?

I just rebuild a 250cc Polaris trailblazer and have spark, fuel and compression but it’s not sputtering or firing up, is it possible it’s the timing, the timing mark is on the factory marker. It’s been bored out, oil pump removed so it’s premix, completely rebuilt engine

Can u help me,I'm learning to fix my dio,it's now in 6 pin cdi and it moves backwards,

to be safe just tickle the pick up point that's it haha

FİZİK DERSİ

1 question, if i upstroke my 2stroke bike by changing a longer rod. So my factory ignition on the bike will be advance or retard?

انا من دوله عربيه اتمنى ان تضع ترجمه

🏆

Hi, nice work, one question wean you mean retard inition you mean rotate stator anticlock and advance inition timing anticlock wise ?

Hi,it’s pete again from the uk,you have got me so interested in these type of bikes that I have just gone out and bought an MBK nitro 50 two stroke,the fireblade and my aprilia adventure bike have been moved to the rear of the workshop along with the motocross bikes,I haven’t worked on a 50cc two stroke since I was 16 some 45 years ago,I’m going to modify and rework the engine so I might need a bit of advice from you!,in return for the advice I can make you some parts that you might find difficult to do,(I have milling machines and tig,mig and gas welding equipment,large lathes Ect)you could email me the drawings and I can make the parts and get them too you in a few days,how do you feel about that,regards pete

TERMODİNAMİK DERSİ GİBİ OLMUŞ BİRAZ

MOTOR LA SENKRONİZE ŞEKİLDE AVANS AYARI YAPAN BİR CİHAZ YAPILMALI HIZA GÖRE DEĞİŞK ZMANLAMA YAPMALI.

make a dyno?

If timing was retarded fuel air ratio must be adjusted richer for faster combustion

So I took your advice and I threw a rod thru the roof of my garage. You wanna help pay the charge.

how can I set up points on a 1940s motorcycle with a magneto that has no Woodruff key? it was running till I removed the magneto know it’s never run again

This guy knows more than he thinks he does 👍🏼

I have watched tons of videos explaining ignition timing, but they caused more confusion.... With your explanation I could realize everything so clearly, each step was animated in my mind...thank you soo much

Thanks for your video, I found it very helpful.

Awesome video, I used to think we needed more advance to make a 2 stroke rev higher. I'm modifying a motorcycle engine for a go kart and gave up advancing it for now.

I was wishing there was a calculator like this about a month ago, glad I found this video! Thank you sir.

So the slower the engine the more retarded it should be? OEM manual says -8°@2KRPM. What’s 800RPM setting? -8? -6? 0?

What I know about 2strokes,. Oil goes in gas, gas goes in carburator, airfuel goes in engine, power comes out! Haha not totally, but not alot more, I would like to get one to play with! Maybe throw a bigbore cr80 engine on a scoot! I'd love to have gears on a scoot!! But I been thinking about going electric!! I have enough high, extremely high current lithium batteries to build a 32ah 72v battery, capable of a sustained 800amps! And 1600 peak amps, 20 series cells , 4 paralell, that's enough wattage to supply over 18hp, with insane torque! It would be like a supercharged turbo diesel, 16hp engine, a 3kw motor on a bicycle would do 50mph+ so a 16kw motor on a little scooter should do nicely! And should only pull around 600 watts cruising at a legal speed, maybe the variator could be used with a electric brushless motor! That could extend the top speed! While keeping a good takeoff and acceleration! I guess I'll have to keep gathering parts, I was thinking about a e bike or E-cycle build, maybe it's an E-Scoot build now!

Cool info man... "Fancy valves".. hahaha

we are using this ignition on a 70cc racing setup. Is ist possible and good for increasing the power, if we turn the stator a little bit more in left or right way? or it just can be measured on a dyno ?

How is advanced spark position found after TDC?

Best explanation I’ve seen! Thanks

There is plenty of BS on web with regards to 2 stroke engines, I watched your video and there is not even a faint whiff of BS, all good stuff! I even spotted that you showed the positive AND negative pressure waves in your exhaust simulation!. BTW I have read A.Bells book many, many times! I'm rebuilding an old Honda MT5 at the moment, its the trail version of what you might know as the MB5. I've had about 54MPH out of it on the flat which is not bad because when they came out in the UK they were restricted to 30MPH :-( I do have some ignition issues at the moment and was looking at the MVT system as a replacement but I need to do more investigating, for starters I need to find out whether the rotor will fit the taper on the Honda's crank, then there is the charging at lighting circuits to sort out too.

hey scott you seem to be very knowledgeable about engine of the scooter. quick uestion if it quick answaer. my started having hard start, now it has been stalling out, now wont start all but sometimes it will but stall again when hit throttle,cleaned carborator, inside all fuel ways passages and float area. i put clear hoses to gas tank to observe what gas is doning. what i have notice the suction of fuel enter the carb line is not being suck down thru the line into the carbis one thing. but two after keep try start it the carb seem to slow flood with fuel some how then i will drain it because it not burning or starting. is something wrong with the vaccum pressure or something

Very nice job, covered almost everything. I was wondering if there is a form or a calculator which you can calculate the settings from the begining with a programmable ignition, at each rpm, just like building an engine from the beginning, without having factory's settings

But.... If timing is based-upon the RPM level, then don't we have to "choose" which RPM we want to optimize timing for? For instance I'm building a 92cc chainsaw (2, actually, a side-by-side build of sorts), and one thing that's BLOWN my mind is how - with chainsaws, at least - the specs always list "ignition timing @X RPM", and then "ignition timing at y RPM" (usually they're Idle and Full Throttle RPM's for the two, respectively) Do you think this means the coil is "smart" and literally doing varied firing-rates based-upon RPM? If so, any keywords you could give so I can learn more? (think I *have* to learn Re magneto's/etc no matter what at this point because I'm doing a "build type" that is pure uncharted-territory) Should mention this coil is NOT one of those fancy new engine-managing coils, it's the same type found on a 1975 chainsaw/blower/weed-whip/etc, I always figured they were "single spark rate" based on their position ONLY but seeing spec pages listing different ignition-degrees based upon RPM has me so confused here!! LOVE how you mention your approach to it IE 'retard it a few deg., advance it a few, see what happens' -- believe it or not but I've NEVER heard the word 'retarded' in chainsaw-tuning, which is so weird because you'd think retarded timing would be pretty critical because it's "needed" for running high compression (a chainsaw build is just a high-compression NA build after all!) Had never played w/ it myself, either, and just received the tool & a couple flywheel-keys (how we advance timing, shaving thousandths off a 'flywheel key' on the shaft), intending to advance timing because "I'm going for power" and as mentioned it's literally the only timing-manipulation I've EVER heard of in the chainsaw world, so weird because it seems so central to all other engine-builds (IE whether timing needs retarding/advancing, and by how much) My engine's OEM spec is 13.1:1 comp ratio so will be aiming to push it to maybe 15:1 if able, limiting factor being piston slapping the cylinder head! BTW I'm glad you mention it but IMO you don't stress just how dangerous/damaging pre-ignition is, knock is hurting power but not the engine, but pre-ignition when there's downward explosions hitting the upward piston as it's nearing TDC is so much worse than knock, I wish I knew that knock was more likely to occur first but don't know 1 way or the other, would love to hear if you do!! Thanks for the great video, when I get to doing mine I'm going to start with a slightly retarded timing to see if it out-performs the oem-spec timing, and go from there til near-optimal (I wouldn't try finding 'optimal' since it inherently means going 'too far' and reaching the point of pre-detonation, will retard it a lil and check, if no improvement I'll begin advancements -- thankfully my platform is a popular one and 20thou off the key is a 'standard' so I know "the range" and would probably begin trying a 5deg advancement and seeing how it went ;D )

Amazing thank you that was really clear

Great vid,thanks you sir👍✌️

Great as usual. Keep it up my friend

Hello i wanted some help with this i have 70cc kit on my aerox and stock ingition and it was running and it just stoped and made a noise at the ingition and everyone is saying its off timing i looked everywhere no one can fix it i hope u can help me with it what to do!

Hey, nice video. My bike makes “knocking” sounds from the engine after changing to MVT dd. Do you know why? Is it wrongly timed or why does it knock like that. I don’t think it’s very damageabke because it disappears as fast as I hit the gas. So it only knocks on idle

Hey man. Dunno if you still read comments on this, but i could use your help. Do you still have a fan for an ac engine and could you try fitting it on the mvt and see if the holes for the screws match? Thanks.