Tomos shifting

OK, so I think I've got something new and cool.

I've been shifting my tomos from 1st to 2nd using my kill switch. It shifts SO much quicker than when I would have to blip shift it using just the throttle its UNREAL.

it's a kitted a35 with the 64cc airsal reed kit with the sport touring head from treats, doppler er2 single reed, 14PHVA with modified stock tomos airbox, hunter pipe, parmakit box, the $33 clutch shoes from treats with 9.5lb springs on 1st and 2nd gear, blah blah blah.

So ok, now that you know the setup, lemme tell you about my situation. The killswitch I'm using is just a momentary killswitch, so it only kills the ignition as long as the button is depressed. Once i've revved out as high (or as low) as I want in first gear, I push my killswitch for a split second, reset my throttle to like 1/4 - 1/2 throttle depending on how high I've revved. The motor drops right into 2nd gear and off I go. Not only does the bike shift faster than when I would blip shift, I can shift at much lower RPMs then normal as well..its kinda wild. I'll eventually pull the tachometer out again and see exactly where I'm able to shift, but if I had to guess I would say i'm able to shift anywhere between 7000 rpm and 9000 rpm in first gear instead of only between 8500 - 9000 rpms like before.

Does anyone else do this? Has anyone else heard of this?

I'll try to get a video soon, but its like harder than normal to film cuz I need both hands to press the kill switch and control the throttle.

Re: Tomos shifting

Probably Fred /

I blip shift well not really I just back off to shift on takeoff if no traffic is on my butt!

moped army posts are not correct For troubleshooting most times I would say almost never have any kind of failure

But I got twice the amount of years of mopeds that Moped army Has and have no failures! I mean you could ask my wife she hasn’t had to pick me up for almost 6 years and when she pick me up I was so stupid one blasted air in the magneto area and I was on my way

To me all my bikes (And cars) could take me anywhere without failure

when people say Moped’s aren’t reliable none of those are my bikes I can’t believe something that only has three things to diagnose have no idea how to troubleshoot them!

Re: Tomos shifting

campeona del mundo /

very interesting research rxb

Re: Tomos shifting

Totally normal JBOT /

I never thought of that but it makes sense.

Use all the tools at your disposal

Re: Tomos shifting

yea, the rear wheel spinning actuates 2nd gear engagement & it seems like with the engine unloaded from the lack of spark, it really helps it settle down into 2nd gear.

i am gonna have to get the tachometer on there to see what happened when i engage into 2nd gear & how low rpms drop. normally i was seeing my rpms at around ~4500 when i would shift before i knew about this, with 1st gear engaging around 5000 rpms.

it’s all so very interesting to me!

Re: Tomos shifting

♣Slew Foot♣ /

I would hazard a guess your ? Mark spring and second gear return gears are loose from wear.

Re: Tomos shifting

> ♣Slew Foot♣ Wrote:

> -------------------------------------------------------

> I would hazard a guess your ? Mark spring and second gear return gears

> are loose from wear.

ok, so you mean the sprag spring but then 2nd gear returns I’m unsure of. do you mean the pins? or the cruciform that they ride in? or the hub with the sprocket that holds the pins in place?

Re: Tomos shifting

♣Slew Foot♣ /

The inner mechanism the kickstarter roller bearing race.

Re: Tomos shifting

so alright, update

i put an estoril that i had made to be spring mount on this bike today & started jetting. i’ve gotten the tachometer to read just over 10k rpms, but very regularly 9-9.5k at WOT with the new pipe vs the old hunter.

these new rpms have made shifting with the kill switch even more effective.

i was able to shift at 9.5-10k rpms in 1st gear & grab almost immediately back into 2nd gear at 5-5.25k rpms

i was also able to shift at only like 7.5k rpms in 1st & grab into 2nd at 4k rpms with wonderful success.

it honestly is a whole new bike.

here’s a couple pictures :^)

4056322C-BDCC-4415-8AB8-101A0E5F3AE0.jpeg
C0095D93-DC88-4F9D-89E5-13FCFB971908.jpeg

Re: Tomos shifting

🇮🇹💦 Of the Loin /

This is interesting.

I can picture a rough circuit that would automatically do this for you....

Re: Tomos shifting

♣Slew Foot♣ /

Is the plate rainbows on the countershaft. They run fastest right before something goes horribly awry...

Re: Tomos shifting

> ♣Slew Foot♣ Wrote:

> -------------------------------------------------------

> Is the plate rainbows on the countershaft. They run fastest right before

> something goes horribly awry...

sure, whatever you say old man. i’ll pull it all apart today & see if anything is broken or breaking in my transmission but all of my internals were brand spanking new as of like 3-4 months ago?

probably worth it to replace the bushing on 1st gear, check my rollers/the cruciform that holds & the sprag spring.

Re: Tomos shifting

> 🇮🇹💦 Of the Loin Wrote:

> -------------------------------------------------------

> This is interesting.

>

> I can picture a rough circuit that would automatically do this for

> you....

this would kind of rock but i really like being able to choose at what RPM i shift at.

it’s also sort of a dance of resetting the throttle back to the right position for what rpm you are shifting at. either way, we shall talk :^)

Re: Tomos shifting

🇮🇹💦 Of the Loin /

I mean, it would sense the tach line (idk how much filtering would be required) and then open a solid state relay for a few mS once a desired RPM was acquired.

The delay could be set in increments of 100mS to start with.

Man I wish I lived near folks that wanna do wacky shit for no reason, I don't have much motivation without others and nobody wants to get wacky with electronics

Re: Tomos shifting

> 🇮🇹💦 Of the Loin Wrote:

> -------------------------------------------------------

> I mean, it would sense the tach line (idk how much filtering would be

> required) and then open a solid state relay for a few mS once a desired

> RPM was acquired.

>

> The delay could be set in increments of 100mS to start with.

If it were me I'd count rising edges on the lighting coil through an inverting amplifier (you can filter there if needed, but I'd bet it'd be fine.) Sensing the pulse inductively like most commercial tachs do is noisier and not necessary if you're making something custom for one bike.

> Man I wish I lived near folks that wanna do wacky shit for no reason, I

> don't have much motivation without others and nobody wants to get wacky

> with electronics

Word.

Re: Tomos shifting

Also this is a super fun idea; I have a momentary kill switch on my a3 tomos and a very similar setup (44mm airsal, estoril pipe, vm18) , I'm going to try this.

Re: Tomos shifting

more people should try this. it honestly rocks.

here’s a couple shitty videos

rpms read out double because the parmakit fires twice every rotation of the flywheel, but i shift at 0:06-0:07 seconds in the video & my rpms drop from ~7.5k in 1st to ~5k in 2nd & then i’m off on my way towards 9k & beyond

here is just me climbing a steep ass hill starting on the hill itself :^) (edited)

Re: Tomos shifting

TOP GUN™ ANDY ⚔ (LSLB) ⚔ /

This is some real good tech riggy. What tach is that? I really think that the information I most want when tuning a bike is just "what RPM am I really at?"

Re: Tomos shifting

🇮🇹💦 Of the Loin /

Would the ignition coil always be charging at the same time spark is firing?

You could use some optoisolators to measure the presence of a specific voltage along the induction circuit to reduce the noise I think

Also I'm mostly just curious what's the smallest time interval this ignition cutting trick would be successful at (would it work at only 100ms? 1000ms?)

Re: Tomos shifting

> TOP GUN™ ANDY ⚔ (LSLB) ⚔ Wrote:

> -------------------------------------------------------

> This is some real good tech riggy. What tach is that? I really think

> that the information I most want when tuning a bike is just "what RPM am

> I really at?"

I’m using a husqvarna branded oppama pet302 tachometer

here’s a link to a place that isn’t amazon that you can buy it from

https://www.ahupd.com/husqvarna-502711401

here’s a video about it

it reads up to 30,000rpms which is fully needed on ignitions that spark at TDC & BDC (edited)

Re: Tomos shifting

> 🇮🇹💦 Of the Loin Wrote:

> -------------------------------------------------------

> Would the ignition coil always be charging at the same time spark is

> firing?

Not necessarily. Some ignitions trigger on the zero crossing of the ignition coil voltage; the capacitor in the CDI circuit has already charged to its maximum voltage for that pulse. I haven't checked a triggered system to see if the same is true, but I would expect that it is, as this would provide the most energy for the spark.

> Also I'm mostly just curious what's the smallest time interval this

> ignition cutting trick would be successful at (would it work at only

> 100ms? 1000ms?)

That's a great question.

Re: Tomos shifting

> Brian F Wrote:

> -------------------------------------------------------

> Also this is a super fun idea; I have a momentary kill switch on my a3

> tomos and a very similar setup (44mm airsal, estoril pipe, vm18) , I'm

> going to try this.

Ope, technigas next R exhaust, not an estoril, but yeah.

Re: Tomos shifting

i honestly don’t think automating this is worth it because sometimes you want to shift later & sometimes you want to shift earlier, but i’m not here to really tell anyone what to do. also the trail tech vapor has a shift light on it that is set by RPM. my guess is you could just tag on to whatever signal is there that makes the light pulse & use that.

anyways, thanks for coming to my ted talk, maybe i try this with the tomos jammer today.

maybe i put a SHA on this bike today?

maybe i ride my stock maxi today?

Re: Tomos shifting

I think you could automate it simply based off of the output power of the stator, as RPMs increase so does voltage so why not just use that to trigger it?

I do think a lot of the fun would be removed by automating it though. This is a cool idea

Re: Tomos shifting

🇮🇹💦 Of the Loin /

The fun is knowing enough about how something works to then create something to do the cool trick you figured out 😉

Re: Tomos shifting

> Nick MBC Wrote:

> -------------------------------------------------------

> I think you could automate it simply based off of the output power of

> the stator, as RPMs increase so does voltage so why not just use that to

> trigger it?

I'd expect the frequency to be a lot more stable and reliable (re: rpms) than the voltage.

Re: Tomos shifting

Both are fun in their own way! :)

Re: Tomos shifting

> 🇮🇹💦 Of the Loin Wrote:

> -------------------------------------------------------

> The fun is knowing enough about how something works to then create

> something to do the cool trick you figured out 😉

fair enough. I still think the part that I really like about this is that I can choose when I shift.

I need to play with like stronger 2nd gear springs now maybe. I bet it'll let me rev higher in first and maybe then having this be automated could be the move?

who knows? I sure as hell don't be hey, in 3 years when everyone is killswitch shifting their tomos i just want everyone to remember it was me who figured it out :^)

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