Advanced Hemi 212cc Predator Build

[bob58o]

WOOHOO I stumped Bob!

You didn't stump me. The huge Aftermarket (tuned) pipes that work on everything from 79cc to 212cc stump me.
Lol

 

[bob58o]

Pictures.

The "100 (R+M)/2" sticker didn't take.

My calculations, with this here HP boost decal, put me above 6.5 HP and Below 25 HP. Lol

 

[bob58o]

It almost screams DIYGY, no?
http://www.ebay.com/itm/Mini-Bike-c...b7c357c&pid=100005&rk=3&rkt=6&sd=272302233036

 

[chancer]

You notice same seller?
You should contact him directly and get some numbers.

 

[bob58o]

And I DID purchased the Live Axle 4.5" Brake Drum with 1.25" Bore Keyed Hub
and
the 4.5" Brake Band.
http://www.ebay.com/itm/Mini-Bike-K...64cdd75&pid=100033&rk=8&rkt=8&sd=381290311477

http://www.ebay.com/itm/151146880805?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT

What are my options
Cable with return spring on the band?

Or

Rod with using return spring on Pedal?

---------- Post added at 09:02 PM ---------- Previous post was at 08:57 PM ----------

Thinking about supplementing this with a cheap mechanical caliper on the existing rotor.
Cheap band brake plus cheap mechanical caliper???
Good Enough?

 

[bob58o]

My welding is getting worse.

 

[chancer]

It just takes practice.

 

[bob58o]

It just takes practice.

Reminds me of training a new bartender that has no chance of making it it.

ME: "Honey you are going to be fine! It just takes practice!" LOL

 

[bob58o]

Designing the linkage for the band brake. The band has to be better than the nothing I have now!

I'm thinking a cable is needed (not a rod).

Since I have a swing arm....

As long as I secure the cable on the swing arm pivot and allow a little play - I should be good with the suspension not causing the band to tighten.

A spring on the pedal will return the pedal.

Will the band return by itself without a rod connector?
Or do I need a sort of return spring on the band where the cable is connected?

 

[Jrgunn5150]

I'VE GOT NUMBERS!!!! Ok I lied. I have ONE NUMBER!!!

GPS on Phone app says 46.6 MPH!!!

This was about 3/4 mile into a WOT run. I had it up to 42 after about 3/8 Mile, then went up a hill, then back down the hill, after about 3/4 mile, I was at 46.6 MPH and let off, but I don't think it was climbing much anyway at that point.

Working the speed calculator in reverse....

6,606 RPM!!!!!


7.5 Gear Ratio
16" Tires
30 Series TC
212cc Predator "GAB'd to pieces"
350 lb? Buggy

What I noticed. Around 21 mph (3000 RPM) it really started to go.

Is this the TC upshifting? Or my engine making beastly power at 3k RPM? OR BOTH?

Maybe I make the TC engage at 3100 RPM?

My guess would be the former, you probably need alittle RPM to "Get up on the cam" as they say, to where it can start flowing enough to really matter.

 

[bob58o]

So I'm a little confused as to how driving is changed by switching garter springs to engage at 3.1-3.2k instead of 2.1k -2.2k.

Also confused how I want the driven set.
Probably cause I never drove stick.
What spring? What hole?

For best acceleration to max speed on street..
Higher rpm up shift- stay in low longer? NO IS MY THOUGHT

Or
Lower RPM up shift- get into high gear quicker. SEEMS TO MAKE SENSE

 

[Jrgunn5150]

You're backwards, you want the engine to be able to get into the powerband BEFORE the "shift" to high gear. So let it rev out.

Of course, experimentation may show the opposite to be true, but as a rule, it's why drag car's launch at higher rpms and shift just after peak power.

 

[bob58o]

You're backwards, you want the engine to be able to get into the powerband BEFORE the "shift" to high gear. So let it rev out.

Of course, experimentation may show the opposite to be true, but as a rule, it's why drag car's launch at higher rpms and shift just after peak power.

This has always confused me a bit. I plan on playing.

I'm guessing more HP but less Torque if I engage at 3200. Which spins the wheels???
This also has to be worse for the belt as the wheels have to catch up with the crank.

It sounds like you like the delayed engagement with a delayed up shift as well... At least worth trying for my top 1/8 mile , 1/4 mile speeds???

 

[Jrgunn5150]

Think of it like this, if you were driving a manual transmission car, would you just go from idle, straight into top gear? Allowing the engine to run up through it's powerband is the reason why we have gear's, otherwise we'd weld our cranks to our tires and zoom down the road lol.

 

[bob58o]

I've got two driver options, 6 driven options.

12 future tests!!!!
Timed at 1/8, 1/4, 1/2 miles!!!!

I'm such a nerd!!!

 

[Jrgunn5150]

I've got two driver options, 6 driven options.

12 future tests!!!!
Timed at 1/8, 1/4, 1/2 miles!!!!

I'm such a nerd!!!

It's all in the name of science.

And seriously, without testing and some kind of protocol for repeatability, you have no idea if you went fast or not truly.

 

[Poboy kartman]

I've got two driver options, 6 driven options.

12 future tests!!!!
Timed at 1/8, 1/4, 1/2 miles!!!!

I'm such a nerd!!!

Well...Bob....I could probably help you....BUT...I don't want to peruse 70 pages of Encyclopedia Jr. to find your cam specs....refresh my short term memory....(Cliff Note version please....)

 

[leesiel]

Love the G A B sticker Bob !

 

[Joe-405]

so how's your project coming there Bob ???? Mine still sucks. Hahaha. Lol

But to answer your question I just took the bar stool from 1900 RPMs to 2900 RPMs and it's actually a lot faster. The ideal time for it to shift into high gear would be right after the peak torque RPM of your motor

 

[bob58o]

Well...Bob....I could probably help you....BUT...I don't want to peruse 70 pages of Encyclopedia Jr. to find your cam specs....refresh my short term memory....(Cliff Note version please....)

Sorry if sideways.