My New Streaker Kart

[ezcome-ezgo]

Yeah those are racing rain tires. Sometimes there are used ones on eBay. They do complete the look.

 

[chancer]

I know these are not rain tires but this is a sweet deal.
16 NEW race tires for $249.00 That is like 15 bucks a tire.
http://www.ebay.com/itm/CASE-16-PCS...010848?hash=item3f5de1ade0:g:-p0AAOSwwpdW25O1
Compare at $600.00 for 16
http://www.ebay.com/itm/Bridgestone...ash=item2cadb531e3:g:PX8AAOSwnFZXWhxE&vxp=mtr

 

[MrC.]

I am having concerns about gearing now. I have the comet 30 with a 9 tooth sprocket running 420 chain to a 54 which gives me 6 to 1. I am trying to understand how the comet effects the gear ratio. I understand how it starts; a small pulley to large pulley then goes to 1 to 1 about mid way through then to a large pulley to a smaller at top speed. So I have the basic understanding of how it works. What I don't know is how it effects the gear other than it goes from lower to higher.
How Low is it? 13 to 1 or 10 to 1 IDK. what mathematical formula do you use to factor a TC?
I want to slide and spin these tires with ease.

This kart had wide 18 inch tires and 5 HP engine from the factory.
Now it has a mild 6.5 and 15 inch tires and a less weight.

Q. should I gear deeper to meet my goal of top speed 35mph and crazy sideways fun?
If I need more gear a jackshaft will be needed, ground clearance is becoming an issue since I drive in grass and not asphalt with the 54 drive gear.

Any thoughts
MrC.

 

[MrC.]

Update
worked late into the morning last night.
I Installed new 13x5-6 front tires and the new 6 inch rear keyed on wheels with some old 15x5.5-6 tires I had. Rebuilt the comet with new bearings and 5/8 shaft. Switch motors and put much 212 predator on it. Fabed up a cable. I changed the main jet to a 38 but thats too rich for my stock engine it just loaded up. It ran but not good. I swapped back jet and rode again. Much better. I think it needs more gear it has a 9to54 or 6 to 1 may be 7 would be better. I was not able to wind up the motor top end it was still pulling and it was fast but suffered brown low and in the corners. Pictures coming soon.
MrC.

 

[MrC.]

Went back out to the shop and made an 8t sprocket for the comet TC. It helped but not right. Felt and heard engine get to higher revs but not floating valves.

Issue #1. Sitting still at idle. Floor it and will chirp the tires on concrete. The TC seems to shock the tires once im moving it performs correctly both driver and driven work correct as in expand and contract. I still dont feel that its right its got top end but less bottom end than I want. Its a new belt and I cleaned the sheaves my are steel and pitted so I wire brushed instead of buffing.

Issue#2 can I change the hole in the TC for more revs down low? If so which hole do I put the spring in there are 3 its in the middle now.

Also the 38 jet with open airbox was to rich can I get more out of this engine with a open airbox and not the k and n style filter?

Thanks
MrC.

 

[mckutzy]

On my bike I had to re jet the carb. With the stock filter/jet, my airfilter adapter mod made it run a bit lean...
I did notice a bit more of performance on the butt dyno however...
Maybe it had created a bit of "ramair" or "velocity stack" effect, but it needed the rejet...

Im still running it on the half-cock position of the choke but other than that it runs great.

 

[MrC.]

Setup so far.
I adjusted the spring in the driven to the third hole it was in the first hole. The spring had green paint on it. I dont know what that means. Clean everything and went door a ride. It is a little better. Still not where I want it. Needs more power maybe more gearing im at 6.6 to 1 with a 8t to 54. I may older a 60 drive gear but I am running out of ground clearence with 15 inch tires. As much as I'd like to go to a 13 inch tire I dont think the brake and gear would clear. I ride in the grass and dirt. Also I opened up the stock airbox. Gotta love a dremal tool.



MrC.

 

[chancer]

I run a 72 tooth (#35) and 13" tires. 1.5" clearance.

 

[Kentucky Boy]

You can swap the 10" brake disc to a smaller one. I use the 8" and it works great. Could probably even get by with a 6" and still have stopping power. Not much you can do about the sprocket clearance though without much work and more parts. The 10" brake disc was just too big for me. Also from the pic of your torque converter looks like your belt has stretched quite abit. That can affect your power feel.

---------- Post added at 11:46 AM ---------- Previous post was at 11:36 AM ----------

Why the rejet on your stock motor??

 

[MrC.]

Hey Kentucky you may be right about my belt either deing wrong or streatched this is a comet 30 with belt # 203589 at least that is whats on it now PO. Someone tell me about a 7 inch driven vs a 6inch. How much lower would the gear be with a seven?
http://m.ebay.com/itm/30-Series-Tor...ch-Go-Kart-Mini-Bike-/272242279640?nav=SEARCH
I want more gear if this wont do it than im looking at a bouble jackshaft and tav 30 with 15 inch tires.

Interestingly the driven is marked with a 20 but the plastic cover says 30?

MrC.

 

[Kentucky Boy]

Mine has a 20 on it to. Our stuff is exactly the same. It's a tav 30. If you need more power if suggest modding the motor more.

 

[DeathMachine]

The 20 refers to the ramp angle on the driven pulley.

 

[MrC.]

Thanks fellas. Your both right. This is my first TC so im learning as I go. I just got a new belt today hope to put it on along with a new green spring and some of those rubber bumper things on the driven.
now I have been thinking if this setup doesn't work I wonder what would happen if the driven didnt open up so fast the gear would stay lower longer. Just thinking out loud here. I want this thing gear low so I can do donuts and get sideways. You know fun stuff. Thats why I keep talking and more gear.

Next will be a stage 1 for my 212.

MrC.

 

[Kelly Wood]

They're just racing kart rain tires... fronts to be exact.

 

[MrC.]

Thanks kelly.
well look at the difference with a new belt. It measures a full 1/8 wider.than the old one.
I was missing the two machine bushing in the driver I am betting that the driver was rubbing the belt at idle and wearing it down. Also notice there not so much play in it either.
Only negative I found was how little the driver face has contact on the crank.
Can ride till the a.m. but I bet this make a big difference.

thanks for all your help, im getting there slowly. I just want it to preform right then start the pretty stuff. I do want to build a dropped front beam one day and get the nose down.

MrC.

 

[Kentucky Boy]

You can either order the two washers or a new back plate that goes on the crank. I did both but wound up using the new backplate without the washers. The new backplate was thicker and didn't need the washers. I have the washers you need. You can have them if you want.

 

[MrC.]

Thank you Kentucky, I appreciate the offer but I bought the two machine washers from MFG along with new buttons and a belt and spring. I will ride it this afternoon and will report back.

The only other change I might make to the drive line is a 60t sprocket and 13 inch tires. currently I have a 54t and 15 inch tires.

MrC.

 

[chancer]

Making that gear and tire change will lower your top speed. But it will be easier on belts and give you more Low speed Torque

 

[Kentucky Boy]

Use some red locktite on your torque converter buttons when installing them. Here's mine, almost finished.

 

[MrC.]

I think that might just do it chancer
just came in from a good thrashing. Everything felt nice and wow what a difference.
no longer does it lurch forward and is smooth and seems to have plenty of grunt.

On flat asphalt I could wind her out but up small hills and in grass I could not.
so I think the 13 tire may just do it. The bulk of our riding is in grass and on trails.

What are the real power gains from a intake, header and jet. Are we talking a horse power or may be two?
If so that would be a 30 percent gain. That would be noticeable.
Mrc.