Not reaching top speed

GoldenMotor.com

Slogger

Member
Sep 8, 2014
544
4
18
nohio
Back to the single prong? Why?
Because three prongs for 1 spark ?? Those extra objects could be acting like oil collectors. Spark plug technology reached its zenith with one prong, and would also be much easier to gap. I bet a new Rolls Royce's factory spark plugs have one electrode. A lot of these doodads are basically a bunch of hype, but you do what you think is best. It's your bike.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Its not the Echo oil, the oil Echo puts its name is excellent oil, you arent gonna get it right until you jet your carb down some, plain and simple.

all the other things you try won't fix a super rich running condition, put a new spark plug, rejet the carb and keep running the Echo oil, you will be waisting your money going to buy a different oil 2hen I can garrantee that has zero to do with why the plug is so black and oily.

Second thing is running a super oily mix for a break in period being neexed is a myth, I start mine up on day one with a 100:1 mix of Opti2 run it for just a few miles to make sure everything is right on the bike and that everything stays mounted as it should and then before the firat tank is even done I ring it out and ride it like I plan to ride crom there on out.

I put about 12-15 miles of easy to moderate running just making sure things are right and then run the dickens out of it after that, I jet my carb down to where I think it needs to be before I ever start a china girl for the first time, to be completely honest about 95% of the "breakin" stuff I read on here is 2hat we call "hog wash" down here in the south...lol Just extra trouble with no benefit at all if things are done right the first time.

Again, reduce the main jet in the carb, adjust mix ratio to 40 or 50:1 with the Echo oil in Regular unleaded ggas and you'll see it come alive as long as you getting a good strong spark and engine has good compression.

Sick Bike Parts has replacement jets if you need to buy them, some of us here just solder our jet losed and then redrill with a proper wire gauge bit until we get the deaired tune for our set up.
 
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YesImLDS

Member
Jun 29, 2013
960
12
18
Columbia, Missouri
What you need to do is get your oil mixture right and then get a new plug and see what it looks like after you run it a little bit to see what you need to do to get it jetted right. You want a tan color plug. White is lean, black is rich
 

Davezilla

New Member
Mar 15, 2014
2,705
10
0
San Antonio Texas
Each engine will run where it wants to when it comes to jet size and you can also buy 2 different jets of the same size but they will measure different, this is why we recommend soldering the jet shut and then drilling them with a #74 to #70 drill bit, the larger the bit size number, the smaller the bit size...
On a bone stock engine with no other mods done it should tune in at #72 or 73, but this has to be confirmed with a plug chop with each jet installed to see which one will give you that nice kinda dark tan color on the tip.
If you need a good plug that don't cost an arm and a leg to tune with, the Autolite #275 plugs are cheap, they work great, and you can either continue to use this plug after tuning or buy a platinum or irridium plug once everything is in tune, the irridium and platinum plugs won't offer any better performance but they will last a LOT longer. NGK plugs are the best brand out there as far as quality goes and you can run standard NGK plugs with no problems if you don't want to pay for the expensive irridium ones.

If your main jet is too rich, your engine will never see a good top speed because it'll be fighting too hard to burn the fuel and will also blubber along and not run clean. You definitely need to run the right jet size for your engine to get it to run right.

Your fuel/oil mix also needs to be properly mixed per what the oil is designed to be mixed at. The Echo oil is really good stuff but it has to be mixed at a sensable ratio or it'll foul your plug quikly. 40:1 or 50:1 with the Echo oil and properly jetting your carb will do wonders for your engine... Once you get it properly tuned with the right oil mix in there it should easily keep up with your friend's bike or even be quicker.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
Ill try jetting my carb! do y'all know any good videos on how to do so?
as far as I know there are no Youtube vids showing the process, I have been planning to make one myself for a long time just for those who are not sure how to do this simple mod.

a small prpane torch, some small solder, some pliers to hold jet, some wire gauge bits and just a couple minutes is all it takes... I know this makes no sense when you haven't seen it done.

its a very simple thing to do when you have the small bits to redrill the jet, I have found that all my engine run great with the jet drilled with either a #72 or #73.

If no one else does it soon, Ill dig up the two links I always post for people so they can get the bits and a pin vise reL cheap to do the job, less than $10 for all of it if you have a small torch and a roll or coil of small solder.

Ifyou use old jet you should spray it off good with some carb cleaner cirst and let it dry a minute or two since any ojl may keep solder from sticking to jet, it only takes a very small amount of solder also, just enough to fill hole and thats it.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
First thing I'd ask is how many miles on this engine? It's going to run bettter, produce more power as the miles accrue. Less than about 200 and you're nowhere near broken in.

Second, I'll suggest you replace that "upgraded CDI" with a stock unit and give it a try.

Have you confirmed that the throttle is opening completely? Incorrect throttle cable tension might be keeping it from opening. Also confirm the choke is open, and staying open.

Put the end cap back on the muffler. You're not doing yourself, the engine or the hobby any favors by running open exhaust. Unless you live in a very rural area with no close neighbors riding on city streets will only bring unwanted/negative attention.

Tom
 
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thirdorangutan

New Member
Mar 19, 2015
74
0
0
Austin, Texas
it has about 125 miles on it. It runs the same no matter what cdi, I just got that one for free. The throttle does in fact open all the way and my choke states open. I put the cap back on yesterday and see no difference in speed between on and off so ill keep it on.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
125 miles is going to put you close to being broken in but the more the better. The piston rings seat better as they accrue milage which raises compression. I agree with the recommendations on lowering your oil content and replacing the 3 electrode plug with a better one.

I wouldn't get too excited about doing any major engine mods until you've determined if this engine is worth it. Most experienced builders will tell you that occasionally you'll find an engine that is just 'a dog' and never will perform as well as others. I've had one that no matter what I did to it it simply never produced the power that my others have.

I didn't see anywhere in this thread about rear sprocker size. What is yours? And if I'm not being too personal, how much do you weigh?

Also how are you checking your speed?

Tom
 

thirdorangutan

New Member
Mar 19, 2015
74
0
0
Austin, Texas
Im using an app that uses gps to test my speed. Ive tested it against a car speedometer and it pretty spot on. My rear sprocket is a 44 tooth. Im just getting out of breakout and getting some fresh gas today. I weigh 105 so that shouldn't be a problem.