Not reaching top speed

If you reduced the oil and lost speed that tells me you lost compression. A heavy oil mix will increase compression. Either your piston rings have never seated or you're loosing compression somewhere else. My guess is the cylinder head/gasket.

If you've confirmed that the piston rings aren't broken and there are no scratches or gouges in the cylinder then the compression loss is either poorly seated rings or leaking head gasket.

Do you own or have access to a compression tester?

Tom
 
Order up those wire gauge bits and solder that jet and drill it.

More oil would have made you leaner too, so all events lead to the same conclusion, you're too rich.

These motors are not built with anything even close to precision, that's why we tell you to solder and drill. You can't just order up a proper jet with any hope of it being right.

You have too much gas and not enough air, simple as that.

Sometimes they even forget to put the jet in the pipe, it's really that bad - :)
 
the speed carb will come jetted to rich also, solder, and drill jet with #72 or #73 clean or replace spark plug, take it for a couple mile ride and go back home, let engine cool for 30 minutes, remove spark plug and see what color it is, if its a nice medium brown and the engine sounds and runs good you're in business.
If plug color is light gray or white colored, you're to lean and need to drill jet to next larger bit size and repeat the process.
 
thirdorangutan said:
Why would it loose speed when I changed the oil to gas ratio?
Click to expand...

less oil more gas in the mix equals an even richer mix, running to rich on fuel is the same thing basically as running an engine with the choke 1\2 - 3\4 of the way on, to much oil can limit combustion ability and to much gas compared to the amount of air in the mix is basically flooding the engine down since it cant combust the amount of fuel its getting fed.

Likely at least one of the reasons the engine is running so weak already is because the jet in the carb is allowing way to much fuel into engine, you reduced the oil so now even more of the mix going into the engine is gas.

Im not for sure yet that this is your only issue, but based on what you've said your plug looks like and the combustion chamber in the head looks like, its a purdy sure bet that a very rich run condition is at least part of the problem and could be most of it, reducing the main jet orifice size will be something that will show an immediate change in the right direction I'm sure.
 
Now that we know its running really rich, what number bit should I start with when Im drilling it. I did some research and it said a number 72 is pretty standard but mine is running super rich. Which should I start with?
 
72. The size of the new jet doesn't depend on the size of the old one.

Go to the hardware store and get those drills. You can use the drills to see what size they have in there now. That will be good info to know.

You really have the easiest problem to fix. At least you're not too lean which can be caused by a host of problems that are much harder to fix.
 
I've already ordered them, but they get here in mid April. Little too long of a wait. Do you think home depot or lowes has them? If they do, I'll cancel my order.
 
thirdorangutan said:
do y'all know what size diameter in inches the #72 bit is?
Click to expand...
I would highly recommend that you just buy the Dellorto jets
and do not mess with soldering and drilling jets.

The #72 drills a 63 jet
Some 68, 66, 64 and 62 jets will cover you.
I would try the 66 first as the stock jet is a 70.

Only $2.50 each from Sick Bike Parts.
http://www.sickbikeparts.com/catalo...ucts_id=116&osCsid=e5kj8fd6algc5r98oa555tcj90


#BitSize Inches Millimeters Jet Size

#80 0.0135 0.3429 34.29
#79 0.0145 0.3683 36.83
1/64" 0.0156 0.3969 39.69

#78 0.016 0.4064 40.64
#77 0.018 0.4572 45.72
0.5mm 0.0197 0.5 50

#76 0.02 0.508 50.8
#75 0.021 0.5334 53.34
#74 0.022 0.5715 57.15

#73 0.024 0.6096 60.96
#72 0.025 0.635 63.5
#71 0.026 0.6604 66.04

#70 0.028 0.7112 71.12
#69 0.0292 0.74168 74.168
0.75mm 0.0295 0.75 75

#68 0.031 0.7874 78.74
1/32" 0.031 0.7938 79.38
#67 0.032 0.8128 81.28

#66 0.033 0.8382 83.82
0.85mm 0.0335 0.85 85
#65 0.035 0.889 88.9
 
another name is index drill bits that i got local. i put mine in my drill press and spin it by hand. 80 percent of it in backwards rotation.

try the solder but its not easy. your going to want atleast 2 bit kits
 
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