Bike Running Horribly

[Alexmeow]

Could it be running too rich because the electric parts aren't working right and are burning up the fuel?

 

[Steve Best]

Could it be running too rich because the electric parts aren't working right and are burning up the fuel?

No, running rich is a carb jetting problem. Spark problems are either NO RUN or INTERMITANT RUN.
You will like the 32:1 to 50:1 synthetic oil mix because it is very little smoke to draw attention.
The plug you need is readily available, any of these will get you running:
BR6HS
BR7HS
BR8HS
B6HS
B7HS
B8HS
The number is the heat range.
Any small gas shop, auto parts, motorcycle shop, even some hardware stores carry these.

You must repair all the messed up stuff like your broken wire, plugwire clip and carb barrel peg if you want your engine to work right. If it is not right, fix it. The wire unscrews from the CDI, cut it back. Get a new plugcap at the hardware store and a new carb is $20.

Steve

 

[Frankfort MB's]

Steve summed everything up

 

[Jeffrey gagnon]

Ok dont know if this is the right place to post this but here it goes i have everything stock with the exceptions

32 tooth sprocket

with what was advertised as a 16mm keihin carburetor clone after measuring the ID it actually is a 19 mm

i also have a dual boost bottle kit (which has worked to my liking so no need for people to comment on that).

Trimmed the piston skirt on intake side

Ok so heres my issue which i believe is a jetting issue (too lean) so i get the bike started and at first it idles fair just higher then normal can only get it to idle just under 4000 rpm once it is warmed up theres times when at a stop where it can go in the range of 5500-6000 rpm i know what everyone is going to say (air leak) i dont believe this to be the issue under a compression test it hit about 130 psi and holds needle doesn't go back down until i release the compression if it where an air leak wouldnt the compression go down and not hold? ok so more details so after bike is warmed up i only get pull up to 3/4 throttle open after that it just has no more pull which will only top me out at 32.9 which leads me to believe i need a new jet but am unsure on if its too rich or too lean i have the c-clip on the secound to richest setting.

 

[FurryOnTheInside]

Lean? Check your intake pipe. Thats the leak "everyone will say". Spray carb cleaner on it. Try it with some choke. Does it run better or worse with a bit of choke?
And probably should have made a new thread but nvm.

 

[Steve Best]

Hi Jeffery,
The carb is measured at narrowest point deep inside, typically where the needle goes through,
much like this drawing shows:

As for the boost bottles and the haters, no worries.
I've had Yamaha and KTM motorcycles that came with them stock.

Have removed then to see their effect. A good system works.

So, for full throttle jetting, how can you be sure of the jetting?
First off, check diligently that everything else is right:
- no leaks at the carb, crankseals, gaskets, engine case.
- sparkplug gap is right, makes a bright yellow spark at rpm
- carb float is set right, no dirt in bowl
- Tank screen or filter is clean, plenty of fuel flows to the carb

Buy a new plug in the heat range you have been using. Give the bike a few full throttle runs.
Pull the plug and have a look. It would be nice if it were as simple as this:

but this is not where you need to look,
you need to look deep into the insulator:

To do so, the experts often use a bright light and a magnifying glass.
When the mixture is very rich you will easily see the huge amount of soot,
but as it gets close to optimum it gets very hard to see the "mixture ring".
So what do we do?

Cut the plug to get a better look:

Here is a good progression to give you an idea of what you will be looking for:

So one more time, someone else describing what you need to do to determine jetting:

And here is one of the best graphics I've seen on reading a plug:

Here is an excent slide show to understand carb tuning:
http://www.slideshare.net/J.T.A.JONES/carburetor-theory

Steve

 

[Jeffrey gagnon]

So, for full throttle jetting, how can you be sure of the jetting? Steve

So the reason i mentioned the fact of jetting is because i have my throttle marked at idle, 1/4, 1/2, 3/4 and, full.

So i get it all the way to 3/4 throttle and after that theres no more pull and from all the posts ive read on here they tell me that 3/4 to full is all the main jet and if your lacking power in that range a richer main jet would be needed.

Lean? Check your intake pipe. Thats the leak "everyone will say". Spray carb cleaner on it. Try it with some choke. Does it run better or worse with a bit of choke?
And probably should have made a new thread but nvm.

It does tend to lower the rpms but then it feels like it wants to die. Also would like to note that when i use the stock nt carb that it runs perfectly fine other then the nt carb leaking gas from the float bowl it works better then this new keihin carburetor clone.
Here is a couple pictures of the spark plug bpr8hix

 

[Jeffrey gagnon]

Also forgot to add that my engine gets really hot after a 5 minute ride to the gas station. My friend was with me and his head was nowhere near as hot as mine. But from what ive been reading this overheating is due to a lean air fuel mixture

 

[Jeffrey gagnon]

Ok so i removed boost bottles and lost on performance but thats beside the point i removed them to level my carb better with original intake neck. I also did a WOT plug chop heres what the plug looks like

I also recorded a video of how my bike idles i put on youtube heres the link


When it revs im only barely touching throttle and it takes some time for the rpms to come back down so if anyone can tell me if the idle sounds right. Also by ditching the boost bottles i can only hit 25 MPH i had a 36 tooth sprocket and was able to hit 32 MPH at WOT now i can only hit 25 MPH with a 32 tooth sprocket at WOT

 

[Frankfort MB's]

Your running lean I'm pretty sure