A Dingos Tale part 2

[Whitetrashrocker]

Perhaps your not close enough to the border. Gotta put a hard vato accent on it.

 

[Whitetrashrocker]

NumberOne needed some love. The breather has been making a mess. So I found an old fuel filter off my jeep and going to see how it works as a catch can.

 

[Whitetrashrocker]

Burned some gas and made a few laps and did a gps speed run down the road. What a bummer. 37mph max. I'm thinking it was sitting on the cdi limiter.

Here's a question for you bobO, 18" rear tires. 17/40 sprockets. I'm assuming 4th gear is 1:1
What engine rpm is that?

Seat felt warm on my back.

I'm gonna have to wrap the pipe and or make a shield.

 

[Whitetrashrocker]

And Denny your right. Put the brakes on the pedal.

Let's see how this works out.

 

[Denny]

I hate it when I’m right. But it will be easier and safer for you.

 

[Whitetrashrocker]

Made a little more progress.
Got the pipe wrapped with a remnant i had. Hope that helps.


Still had some frame flex from the floor being only the 2 rails.
Again raided the scrap pile for some old reclaimed water pipe. Put a bend in them and made upper rails.

 

[Whitetrashrocker]

Also picked up a "performance" cdi box. Ohh it's orange!.
Put it on and it was hard start.
Put my dumb timing light on it and I saw two marks with no indicators.
The flywheel has 4 marks on it.
"T" for tdc
"F" for fire. The stock cdi box fires here.
Then a few inches around are 2 unnamed marks. I had tondonsome digging and found on a different Honda flywheel they put 29° and 32° btdc.

I borrowed dad's smart light.


It didn't like the cdi and or the wasted spark.
Said the rpm was 3200 at idle and very jumpy.
Don't sound right.
With the stock cdi I could delay the flash and get the T lined up. Said 20° that seems alot.
Popped the orange box in and it went to 68 or 70° advance. Again i was confused.

Laying in bed insomnia is my best thinking.
Duh. Wasted spark. I have to half the numbers.
So I'll throw out the rpms. And the timing would be like 10° at idle with the stock box, seems more like it. And the orange would be closer to the 28 -30°

I'm sure the orange box just eliminates any curve and just full advance. Haven't road tested it yet. Supposed to have removed the rev limiter too.

Deep research says the stock cdi boxes perform better than the various colored hot rod ones do anyways.
It was 9 dollars. I had to try.

 

[Whitetrashrocker]

But wait, there's more!

Just a preview and not my pics but I got a new cam comming. Supposedly here's the difference. Stock on the left.



I'm gonna have to crack it open to see if the cam follower is tappet or roller. If it's a flat style I'll get some rollers comming.

And while I'm in there the heads gonna get decked probably .040". Gonna breakout the clay to find out how much I can go with the new cam. 9:1CR is pretty weak sauce.

Also had plans on hogging out the ports. Apparently the exhaust is super restricted.
Here's a guys work on one's he sells.
Stock vs gasket matched.


Reviews on the cam and head porting are good. Goes from meh to poppin wheelies with no gear change.
Sounds good to me.

 

[Denny]

I have that very same snap-off timing light. Espensive little bugger!

 

[bob58o]

Burned some gas and made a few laps and did a gps speed run down the road. What a bummer. 37mph max. I'm thinking it was sitting on the cdi limiter.

Here's a question for you bobO, 18" rear tires. 17/40 sprockets. I'm assuming 4th gear is 1:1
What engine rpm is that?

Seat felt warm on my back.
View attachment 149774View attachment 149775
I'm gonna have to wrap the pipe and or make a shield.

Just the internal transmission on this one?
No CVT?

(37 miles / hour) x (5280 ft / mile) x (1 hour / 60 min) =
3256 ft per min

18” diameter = 4.7 ft per axle revolution

(3256 ft / min) x (rev / 4.7 ft) = 692 axle rpm

692 axle RPM x (40/17) = 1628 engine rpm

I would assume this type of engine would turn 6500 rpm or more, correct? I’m not missing a primary reduction inside the transmission am I? 1 : 1 in 4th is 1: 1 on the in/output shafts? Or 1:1 is a secondary ratio excluding a primary ratio?

 

[bob58o]

For example… Does this engine with 4.05 : 1 primary reduction and 0.90 : 1 ratio in 5th gear mean the actual reduction in 5th gear is 3.6 : 1?

If there is about a 4 : 1 primary reduction, then in your case 37 mph would be about 6500 RPM.

200CC/250CC ATV Engine Motor Kit 4 Stroke Single Cylinder Air-Cooled ...

Primary Reduction Ratio: 4.055. Transmission Ratio of Each Gear: First Gear: 2.909; Second Gear: 1.786; Third Gear: 1.375; Fourth Gear: 1.167; Fifth Gear: 0.900.

 

[Whitetrashrocker]

Yeah, that's the engine but I have the 4 speed w/reverse. There's several variants.
I never thought about the primary reduction. Good catch.

That 6500 rpm sounds about right. It wasn't completely wound out but just quit making power at that point.

Thanks for mathn' that for me.

 

[bob58o]

Yeah, that's the engine but I have the 4 speed w/reverse. There's several variants.
I never thought about the primary reduction. Good catch.

That 6500 rpm sounds about right. It wasn't completely wound out but just quit making power at that point.

Thanks for mathn' that for me.

Ya just estimating cause 18” tires aren’t exactly 4.7 foot circumference…

But if I said 37 mph was 1692 rpm, with 4.055 primary reduction, it would be 6861 RPM.

And if the tires aren’t a true 18”, like the kart only rolls 4.3’ per tire rotation, then it would bring you up to 7500 RPM rev limit at 37ish mph.

Or if the tires are 4.7 foot circumference but 4th gear is 1.1 : 1 instead of 1.0 : 1 then you might be hitting 7500 rpm.

Or a combo of the two like 4th gear 1.05 : 1 and tire circumference of 4.5 feet would also hit 7500 RPM rev limit around 37 mph.

 

[Whitetrashrocker]

OK. More disappointment. Stole this off the other kart.


Black cdi idles at 900. OK I'll buy that. Then at a full rpm run it kinda topped out at 4k. Hmm.

Bob I measured the tire circumference at 55.5" or 4'7".

 

[Whitetrashrocker]

I put the orange box in and it idled at 1050 or so. That i expected. Made some hot laps and i saw 4500 which is higher than the other box and it felt like it would have kept going. I had to back out. Tracks not big enough.


The larger orange box is adjustable with 8 different curves. I haven't tried it yet. Not sure how to work it. No instructions. No sticker on it. Nuttin.

I had a go on the search for this. I'm still not sure what's going on. Lol




Any one fluent in chinglesh?

 

[Whitetrashrocker]

 

[bob58o]

I watched a video in a language I didn’t understand but I think he liked the adjustable cdi box set with all 4 switches “up” … I guess it is “speed limit mode 8 12k rpm”
Low RPM and High RPM are spoken in English, but I can’t really understand the rest. I’m not sure what the first switch does. Race Mode vs Speed Limit Mode.

 

[Whitetrashrocker]

I played with the adjustable cdi for a few minutes. All down seemed to run OK. Any other position and it ran horribly. Shook badly. Not steady spark for sure. Took it out and put the plain orange one back in. Seems to like that 28° advance.
Low end is alot more spunky.

While I'm waiting for the roller lifters to arrive from mars...
I took some calipers to the cam I got. Surprisingly it was the same in the picture I ordered.



Been doing some internet digging and compiled this. Again info is sparce. This seems consistent with the 3 cams available for this engine.



The stock lift at the cam is 6.1 or 6.2mm. The 1st mod cam is the same lift but a longer duration you can see in the picture.
The mod 2 cam has 7.4mm of lift. But it's tricky cause the took the base down in diameter.

Now duration and overlap? Who knows. I did run across a reddit post. Again I compiled this guy's info. Taken with some salt.



I'm used to seeing the exhaust lobe in the upper left quadrant.

He measured at the valve and not the cam. Not sure what the ratio difference would be either. I think is 1.3:1 but I'm not positive.

And i no comprende m&ms. Wheres the freedom units.

 

[Whitetrashrocker]

Check this out. What do you think.





Same psi. The rounder tire has stuff inside. You can hear it rolling round. Never been flat. Never been off the bead. It sounds like gravel inside. I posted a video earlier and pointed it out. These pics really don't show well.
Im wondering if a belt broke inside.
Any of you seen this before?

 

[Denny]

Yea, it was the way the tire was manufactured. Seen it all the time with ATV tires.