built motor first ride!

[mrfubs]

Hello everyone!
Just got the bike out its running!

#85 main jet, I think the pilot needs to be a little bigger. You can hear when the power band kicks in. Honestly it ran better than I though it would.

Background: Arrow reed valve, puch 74cc hi compression head, notched windowed piston, balanced crank, yz80 exhaust chamber, port matched cylinder and case and 36t sprocket.

Here's video below.
http://m.youtube.com/watch?v=JU1S4NphMEc





New seat and i cut the seat tube on the bike 1.25" to lower the seat more

 

[Enforcerkart65]

That thing sound sweet

 

[mrfubs]

That thing sound sweet

And its not even tuned yet! Also since it only has a coaster brake I just bought a front wheel off a MTB with a disc rotor on it, I'll just have to fab a bracket on the fork

 

[Enforcerkart65]

I did a freewheel cruiser using the front hoop thing from the front of some old mountain bike forks. Also using a dual brake lever and it stops on a dime.

http://motorbicycling.com/showthread.php?t=49016

 

[mrfubs]

Nice I have a dual cable lever as well it seem like a great idea. So I just made a walk around vid of my bike and how well I got the carb tuned atm , the CNS is a great carb it just needs major jetting and a mod or 2.

Here's the vid enjoy!

http://m.youtube.com/watch?v=XvvYXM4G8WE

 

[Enforcerkart65]

sounds sweet, but here in Australia i think the cops wouldn't like that. thats why i still got the stock pipe (as much as i want a massive expansion chamber i can't really). at the moment i got the rt carb and it runs great but u cant tune it which is super frustrating, so i was thinking of getting a mikuni vm18, or one of the many dellortos.

 

[mrfubs]

sounds sweet, but here in Australia i think the cops wouldn't like that. thats why i still got the stock pipe (as much as i want a massive expansion chamber i can't really). at the moment i got the rt carb and it runs great but u cant tune it which is super frustrating, so i was thinking of getting a mikuni vm18, or one of the many dellortos.

Honestly the CNS carb is great I'm using it now, it went from a boggy paper weight to a fully functional carb. Im currently at a 87-90# jet stock was #70. I drilled the pilot jet out 2 more sizes and is working good. You should have a carb with the same size bore as your intake. CNS bore size is 16mm and is plenty for me because me intake tube is 16mm aswell.

UNLESS you have a modified intake that's a bigger diameter. it wouldn't do you and more good to have a bigger carb bore than the intake of what its going on. But it all depends on what motor work you have done too like porting and timing advancements exhaust setups, modifying the piston, its all about flow.

 

[wheelbender6]

You have built a real beast. The YZ pipe is awesome. I think more builders will use the La Jolla frame now that offset intakes are easier to find.

 

[mrfubs]

You have built a real beast. The YZ pipe is awesome. I think more builders will use the La Jolla frame now that offset intakes are easier to find.

I was a little skeptical about buying the bike at first it grew on me its a pretty sharp look for what you get! I will say one thing though, it only has coaster brakes and can be dangerous in emergency situations. I have to come up with a way to braze a alloy bracket on the for a disc brake caliper.

Otherwise its a nice cruising bike!! And light!

 

[mrfubs]

Hello everyone! UPDATE

With in a week i should have a MTB front suspension fork to go along with my disc brake conversion.

 

[dumpstercrusher]

thats a pretty sweet bike! u know the top speed on that thing? how was the fitment on that pipe? ive wanted that pioe before but i didnt know if it would clear the frame so i went with another

 

[mrfubs]

well, it fit just fine actualy! i didnt have to modify the pipe at all with the Kent la jolla frame i used . I cut off just the flange part with the O-rings off and i had a banana chamber i didnt want to use because its lack of size, i chopped peices off that and brazed it all together it works and sounds great!

As for a speed reading i do not have yet. ill letcha know when i get this front fork/brake conversion done so i can actually stop. My buddy rode it and the chain came off so he had no brakes lol the neighbors lawn was his brakes.

Heres the link to my thread of making the exhaust pipe work

http://motorbicycling.com/showthread.php?t=48912

 

[dumpstercrusher]

well, it fit just fine actualy! i didnt have to modify the pipe at all with the Kent la jolla frame i used . I cut off just the flange part with the O-rings off and i had a banana chamber i didnt want to use because its lack of size, i chopped peices off that and brazed it all together it works and sounds great!

As for a speed reading i do not have yet. ill letcha know when i get this front fork/brake conversion done so i can actually stop. My buddy rode it and the chain came off so he had no brakes lol the neighbors lawn was his brakes.

Heres the link to my thread of making the exhaust pipe work

http://motorbicycling.com/showthread.php?t=48912

yea if ur goin with disk brakes its a good choice. love my front disk brake after my build. Love ur bike though! it gets a lil scary goin 40mph on a bike lol

 

[mrfubs]

I ended up buying a shimano hydraulic front brake set brand new 38$ shipped! I also bought a 203mm rotor and am going to buy a RST fork sense there basically the only brand who makes a somewhat quality 1'' suspension fork .

Its gonna ride great and stop great and hopfuly look great!

 

[dumpstercrusher]

nice deal! you should def have some great stopping power wit the hydraulic. well u already have the look down

 

[dodge dude94]

That is sick. Looks like it might be a tad rich on oil. What's your ratio?

Can you actually get your spark plug out of the engine? Looks tight.

 

[mrfubs]

That is sick. Looks like it might be a tad rich on oil. What's your ratio?

Can you actually get your spark plug out of the engine? Looks tight.

Good question haha yes i have a small chainsaw sparkplug wrench/screwdiver tool that fits in there after a few mins of playing Chinese jigsaw.

The oil mix is still at 16:1 break in and is running great with it so far. I have less than a half tank to burn till i switch to 24 or 32:1. I have a gallon of AMS oil Dominator Synthetic left over from my dirtbike that i will be using.

The breakin oil i was using was Klots with 20% castor oil. Best smelling oil out there.

 

[dodge dude94]

Good question haha yes i have a small chainsaw sparkplug wrench/screwdiver tool that fits in there after a few mins of playing Chinese jigsaw.

The oil mix is still at 16:1 break in and is running great with it so far. I have less than a half tank to burn till i switch to 24 or 32:1. I have a gallon of AMS oil Dominator Synthetic left over from my dirtbike that i will be using.

The breakin oil i was using was Klots with 20% castor oil. Best smelling oil out there.

Well, that's why it's smokey.You should be using 24:1 to break in and then you can move to 32:1 or 40:1 if you so desire after it's done with break in.

 

[maniac57]

Well, that's why it's smokey.You should be using 24:1 to break in and then you can move to 32:1 or 40:1 if you so desire after it's done with break in.

Good advice there!
16:1 is far too much oil.
Remember, the factory is only concerned with preventing warranty claims and instant failure, Not with HOW the engine runs.

 

[mrfubs]

Well I have plenty oil it runs great and i know how rough these engines are tolerance wise and feel safer at 16:1 knowing everything is getting plenty lubricated on this low tech engine. The cylinder is only flash chrome plated and is really thin.

Another reason it looks really smokey is because the kind of muffler i am using and 2 strokes just smoke in general! I think I'm going to run 32:1 after it breaks in and it'll probably run a lot better than it already does! Ill keep you guys posted!