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VTECturbo-Bike89

New Member
Mar 9, 2015
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Santa Clarita CA
Both absolutely correct!

It's true that I happen to think that anyone who is serious about learning how to maintain one of these bikes is going to do some searching. After all, waiting on answers is also time consuming.

But if we carried the command to search to it's logical end, then once a question is answered no one should ask it again. That'd be silly. It would kill the forum, in fact.

Going over subjects that have already been covered not only 'hammers out the details' it gives a chance at more food for thought. For instance.......

I just happen to be breaking in a new engine right now. It's only been five days and, probably, less than 30 miles. It's not idling.

I haven't been all that concerned about it. I figure that once I get it broken in, then I'd adjust idle or maybe start messing with my intake. Get it idling one way or another.

But it hadn't occurred to me that a clutch that is not totally dis-engaging could be the culprit. I might have thought of it on my own. But it might have taken me a long time.

I read threads like this, and others, in the hope that I might help. But there's also a subconscious, I guess, hope that I'll learn something too. And I just did.

So a newbie can ask, "What's a spark plug?" and I'll never tire of answering. It's okay. Even if that thread goes no where I was able to be of some kind of help. And if the thread comes alive, then I have a chance of picking up something interesting. That's just fine with me.

So thanks for the flower nut hint. Who was that? Hot Rod, I think.

Yeah I agree with you 100% this forum (along with all) would be pretty lame if we had 1k users searching and never posting. im all about talking it all out as you guys can see from my intro :).

as for the the idle issue, oh man I had one CRAPPY night, let me give the SUPER SHORT VERSION. i rewire my wiring cuz the heat shrink i put on was excessive and nasty looking, then i screw my idle screw in a bit, LITTLE did i realize i installed the throtle cable wrong becase i didnt notice that there was that little like metal pin kind of sticking out inside the bore of the carb and I didnt realize that you had to line up that like dowel pin looking thing that the brass looking needle goes thru, anyways so when i adjusted the idle screw, WITHOUT ME KNOWING, IT OPENED MY BIKE TO FULL THROTTLE!!! AND I HAVNT INSTALLED THE KILL SWITCH! oh my lord, i had to disconnect the spark plug while it was running free in FULL THROTTLE, Jesus that shock really hurt, so i get back to garage, THINKING it was the idle screw, so I tweak it again, OMG SAME THING, ANOTHER FREAKING SHOCK, zpt zpt zptso in panic i pull the spark plug wire off again, this time i got hit even harder because I didnt pull hard enough so I had to shock myself twice, (getting it off the second time) jesus I just wanted to throw the bike away, anyways later that night I realized and fixed the throttle cable now all is good.

Sooo now my current problem im having, after fixing the throttle and and wiring, im not having a random like Sputter/miss-fire that lasts until I let off the throttle and re-throttle... it lasts for like burts of 2-5 seconds and happends maybe every 5-10 seconds.. so im thinking something is really out of tune? could It be something with either
A. The choke? that I have in god knows what position.
B. Something with the throttle cable? (doubtful)
c. Maybe I crossed the black/blue wire (doubtful as I assume it just wouldnt start)
D. Needs carb tuning?
E. (VERY suspicious of this out but sorta doubt it) Maybe I tweaked the idle screw too much? killing the EITHER AIR OR FUEL supply?
F. (again sorry for too many options) but I run 2 fuel filters, 1 bigger one from autozone and the small factory one, both inline -- (reason) I just wanted to be safe with having clean fuel WHILE im still a noob playing around with the oil/gas mixture, and constantly pouring **** into the tank and what not.. Im assuming that 2 fuel filters 1 being a LITTLE bigger wouldnt like trap oil behind would it??


Thanks in advance and im sorry for all the clutter of crap I wrote! I highly appreciate anyone that takes the time to read it :)
 
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bluegoatwoods

Active Member
Jul 29, 2012
1,581
6
38
Central Illinois
"Sooo now my current problem im having, after fixing the throttle and and wiring, im not having a random like Sputter/miss-fire that lasts until I let off the throttle and re-throttle... it lasts for like burts of 2-5 seconds and happends maybe every 5-10 seconds.." --VTEC

If I understand you right, you're talking about something that's not uncommon with these engines. I think of it as 'bogging down'. I also think of it as 'four-stroking' really badly. The engine is actually only igniting, maybe, 1 out of 4 revolutions instead of 1 out of 2.

I experience it a lot when the engine is still warming up. It doesn't happen when the engine is warmed up properly. Does this describe what you're experiencing?

I wouldn't be too concerned unless it keeps on happening and won't stop. To the point that you simply can't ride. And your engine is not reliable under any circumstances.

I believe the cause of this is too much fuel and not enough air getting into the combustion chamber. So, yes, that could be a choke issue.

But I'm not sure if we're talking about the same thing. So I won't make more guesses until I'm clear on that.

It's too bad that the subject of proper throttle slide installation didn't come up earlier. Because a runaway throttle is a terrible thing. But you survived it and now you know what to look out for. One of the things to look out for, anyway. Make sure, also, that your throttle cable is not in a position to get caught on anything that moves while you're riding. Handlebars, for instance. That can cause 'runaway bike' too. (It's happened to me.) And if your throttle handle turns on your handlebars, then the same thing can happen.

Do remember to go slow and cautiously with installation of unfamiliar parts. Easier said than done? Yes. And I do understand; you want to ride your bike.

But it's not really just a bicycle anymore. And it does take some learning to get it right.

So go kinda slow and tinker with these parts a bit before installation. You want to understand them as much as possible before putting them to use.
 
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2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
If you're using the kit supplied spark plug boot my guess would be a bad electrical connection where the wire is attached inside the boot. With you jerking at it to stop the engine (another argument for using the kill switch) you might have compromised the connection. The kit boot is a poor design to start with and pulling it off the plug in a panic could quite possibly result in a bad connection.

The idle speed screw has nothing to do with air/fuel mixture. It is simply a mechanical stop that controls how far closed the throttle barrel can go when you release the twist grip. It isn't a mixture screw like some carburetors have. Screw it in to increase idle speed and out to decrease the idle.

Wire the kill switch like it is designed to be. The two wires from the kill switch (color doesn't matter) should be spliced into the connections of the blue and black wires. That switch is a safety device and should be installed.

Would it be possible to post a couple photos of your bike and engine? There might be other things we can offer some help with to get you going if we can see your installation.

Tom
 

VTECturbo-Bike89

New Member
Mar 9, 2015
46
0
0
Santa Clarita CA
Guess I really need to do that as soon as possible which is posted pictures I believe I have my choke somewhere right in the metal so I'm just going to try both settings for now and see you when I get out of it as far as learning this thing me being a mechanic and sounding like such a newbie is really embarrassing for me it's just that I am a fuel injected the guy I work on imports and I have never been able to messed with carburetors as much as I would like to that's really sad for me to say because I have a 1970 supercharged Camaro that we put together but my buddy did all the carbureted stuff I am a very good fabricator I can weld cut install replace diagnose and all of that but I'm just extremely new to bites all knowledge and tools that I have is all from cars and it has actually enabled me to build this whole bike and about a full days work. Which I would say for how decently reliable I got everything is not bad at all but yes when I get home today I'm going to work on posting all of the pictures of my whole build I documented everything and I really look forward to talking to all of you here if anymore if you have anymore ideas thank you all so much and have a great Sunday or Monday depending where you're at in the world cheers
 

allen standley

Well-Known Member
Oct 22, 2011
1,126
238
63
Bangor, Maine
WELCOME VT 89- Hang in there buddy. When you are ready for it check out my "Happy Chains Album" hopefully helpful! I built 15 bikes and every one have wanted me to throw it in the river at one point or another. You are not alone with these familiar frustrations; but the joy and pleasure compared to cost and maintenance far outweigh the learning curve. I knew jackcrap about these things when I started. With all the help here and persistence on your part there is no issue you will not overcome. Good Luck- above all be safe! http://motorbicycling.com/album.php?u=33548
 

VTECturbo-Bike89

New Member
Mar 9, 2015
46
0
0
Santa Clarita CA
Here's my official build thread! I'll post pics and describe everything after, I'll try to post in order uh ok I can't figure out how to post multiple pics using the manage attachments... So I'll just do one by one in order" sorry for the mess I'll ctrate photo bucket later
 

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fatdaddy

New Member
May 4, 2011
1,516
4
0
San Jose, Ca.
Sweet thanks a lot man, so I'm sitting here really debating if I should run it oil richer more then 32:1 Cuz 4 ounces of oil to 1 gallon gas just seems way too low of oil...
Thats what I run in my daily driver, 4 oz per gallon. Some may say its a little too much for a engine thats already broke in. But its been working for me for years. You cant harm an engine with too much oil, only with too little oil. SO, for break in try 4 1/2 oz per gallon, it wont hurt a thing except it might smoke a little. Looks like the bike is coming along great.
 

2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
Vtec,
Your carburetor is a little off-center. It should be mounted vertical, not slanted. Also you want to get rid of that small spring between the clutch actuator arm and the end of the clutch cable. It serves no useful purpose but it will make your clutch harder to pull.
You might want to move your wiring a little. You don't want it resting against the exhaust.
Everything else we can see looks good.

One fuel filter will do the job but two won't hurt anything. Do what you're comfortable with.

Tom
 
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BOYGOFAST

New Member
Sep 28, 2013
124
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0
Citrus Springs Fl.
some of the most expensive machines featured have a standard bicycle steer tube, that in relation to what is attached defines the machine from thereon most of use don't have the tools or shop to participate yet decide to take the risk that is namely wasting time and money attempting to save both related to topic
 
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2door

Moderator
Staff member
Sep 15, 2008
16,302
175
63
Littleton, Colorado
some of the most expensive machines featured have a standard bicycle steer tube, that in relation to what is attached defines the machine from thereon most of use don't have the tools or shop to participate yet decide to take the risk that is namely wasting time and money attempting to save both related to topic
Nevertheless, advocating mounting an engine with self tapping screws is a disservice to new builders that could cause injury. Please consider your advice before posting. There are certain responsibilities required to build a motorized bicycle. If you do not have the necessary funds or mechanical ability then you should maybe look for a different hobby. This isn't the place to cut corners which can get you hurt or worse.

Tom
 

VTECturbo-Bike89

New Member
Mar 9, 2015
46
0
0
Santa Clarita CA
Man I am totally bummed out about one thing playing with the choke did you get the motor to somewhat idle it still has a big problem and shuts off very frequently unless I play with the throttle but really what disappointed me a lot was the fact that I just realized this bike cannot pull up a hill that's probably about a quarter of a mile long and is unfortunately the way to my house I had to hop off the bike hold the clutch and and freaking walk the bike all the way up the hill home I was really bummed out at the lack of power that it had so nonetheless back to the drawing board who knows what I can do to give this thing the proper low and power forward a slow uphill pulls. Is there anything I can try that's quick and easy as far as may be a spark plug or a carburetor or something that I can locate local to me and California Southern California Los Angeles county area but I can pick up tomorrow and install that should make a pretty big difference
 

Davezilla

New Member
Mar 15, 2014
2,705
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San Antonio Texas
Part of the problem right nownis that the engine isn't broken in so the rings are tight as well as other stuff and the rings aren't seated either so there is also a lot more blowby in the new engine. If you have a smaller sprocket than stock on the rear wheel that just adds to the problem. I would say just run it and keep it close to home for now.
Changing sparknplugs does not add power and a new carb wont help that much since the engine is still really new. Mine would barely crawl up the hill to get home on my street until I went thrum about half a tank of gas it had to be pedal assisted. It does it now with ease. You can also come up to the hill with a running start so the rpm don't dip below the powerband which would also make it incapable of climbing the hill. One quickly fix would be to add a reed valve to get more low end torque and also an sbp pipe would also help with the power. Mine nearly doubled in low end power by adding an expansion chamber pipe a d that's a permanent power gain, the reed halve would give you good low end power now but your top end would suffer unless you also did the piston mods so your engine could breathe at higher rpm.
if you do buy any power adders, go for the pipe first, then add a reed valve if you still need more down low, we can show you how to do the piston mod so the reed will give you power all the way up after the engine breaks in, or if you decide to, you can remove the reed after the engine loosens up if its too sluggish on top or you can cut a window in your piston to take full advantage of it.
 

BobbyT

Member
Mar 16, 2014
162
15
18
Santa Maria ca.
When you remove the thin spring it would be good to put the big spring on the clutch cable to protect it from the cylinder fins. They get hot and can melt the plastic.
You will get more power as your motor gets some miles on it. Have fun, Drive safe, Don't worry.brnot
 

VTECturbo-Bike89

New Member
Mar 9, 2015
46
0
0
Santa Clarita CA
Part of the problem right nownis that the engine isn't broken in so the rings are tight as well as other stuff and the rings aren't seated either so there is also a lot more blowby in the new engine. If you have a smaller sprocket than stock on the rear wheel that just adds to the problem. I would say just run it and keep it close to home for now.
Changing sparknplugs does not add power and a new carb wont help that much since the engine is still really new. Mine would barely crawl up the hill to get home on my street until I went thrum about half a tank of gas it had to be pedal assisted. It does it now with ease. You can also come up to the hill with a running start so the rpm don't dip below the powerband which would also make it incapable of climbing the hill. One quickly fix would be to add a reed valve to get more low end torque and also an sbp pipe would also help with the power. Mine nearly doubled in low end power by adding an expansion chamber pipe a d that's a permanent power gain, the reed halve would give you good low end power now but your top end would suffer unless you also did the piston mods so your engine could breathe at higher rpm.
if you do buy any power adders, go for the pipe first, then add a reed valve if you still need more down low, we can show you how to do the piston mod so the reed will give you power all the way up after the engine breaks in, or if you decide to, you can remove the reed after the engine loosens up if its too sluggish on top or you can cut a window in your piston to take full advantage of it.

Is there anyway to EXACTLY figure out which type of engine I have, because as you have seen my complaints (Norm from VMB) still has not gotten back to me, (like I said, He saved me in his phonebook as "Guy I ripped off for 220 bucks- DONT ANSWER" im certain at it.. I called him from a different phone and he answered, When he did that, IT CONFIRMED for me that he is obviously ducking me for NO reason and I just hung up because it made me never want to speak to him again. Anyways enough up that bad apple- I wanna figure out exactly what I have brand, name, size, etc.. So I can figure out what exact parts to purchase and what not.. how do I go about that?