Bike Build and Some Questions

Chain Driven · Nov 2, 2013

Well, I guess I spoke too soon - I was promptly greeted in the introduction section but in this section it seems the original author of a post replies to their own topic as much as any suggestions or comments are given by others. Maybe everyone expects the people who have questions to search the forum for hours or read stickies for "one answer fits all" solutions. But there are too many makes and models of bicycles to have a one-size-fits-all answer. That would be like telling a guy who owns a Ford truck to read all the suggestions given to people who drive Chevrolet trucks - even though they're both trucks, they are too different for a suggestion for a specific model (especially a generic suggestion) to work for everyone.

That said, maybe people just overlooked it the first time in my initial post because of the long story - I felt that being detailed was important - but there were two questions in particular I need to know before I go just guess-buying things cuz I don't want to waste money, and those questions are:
1) What should I do about mounting my carb? Will the BoyGoFast angled intake work, should I make my own from EMT (if so, how to make the flange?), or ??? [your suggestion]
2) What size is my bike and how can you tell? (this one might be generic but I haven't seen a clear answer)

Also a question not in the original post - Bicycle speedometers are said to fit 26~27 inch bikes.. if the bike is not measured by the tire size, that would seem to be grossly inaccurate, so thats why I want to know how bike sizes are determined - and also for future fitment concerns where I cant touch and examine something I'm considering getting for my bike.

In the meantime, here is an updated picture of my bike, and below it, some notes about what has been installed:

From the first picture of the bike, you can see the biggest improvement towards getting it in running condition was the addition of the derailer. Initially the chain was way too wide to fit through it, but I managed to find some screws and spacers to spread the guide plates out enough for the chain to fit. Its still a bit of a tight fit, if it hangs during testing, I'll see about adding more spacers, but the current screws might not have enough thread. You may have read ealier where I got this chain tensioner, but the round guides on it were way too small to fit the engine chain through it, so I used it on the pedal side to keep that chain from being so floppy.

Speaking of that engine chain, the drive sprocket on the engine is a super tight fit. The chain tries to ride up on top of the teeth because its as if the sprocket is made for chain with more spacing between the links, or the teeth having too narrow of a gap. Has anyone else had this problem? I got it going fairly smoothly around by using a Dremel to reduce how wide the teeth are (that is, making more gap between each tooth), but I wonder if it'll jam while the tension is on the other side of the chain during starting. I tried to remove the sprocket but it's stuck pretty hard.

Next I put on the headlamps and mirrors. It was all a pretty tight fit since the mounts for the mirrors were way too small to put on the end of the grips, and the speedometer was in the way of putting the headlamps on the topside of the handlebar. I've also got the new seat and running light installed. The running light is terribly off-center, I don't know how the manufacturer expected it to be center with the mount way off to the side. I'll probably need to put that on the reflector mount some way, but it has an odd mounting point so it'll have to be drilled or something. Also got the seat cushion put on, but the divot in the middle isn't as deep as I'd like, so while I'm trimming the hole for the brake light, I'll probably take some of that foam out of the middle too.
The last thing to come in was the tire flys, so I got those in place. After some testing on the front tire, it seems the contact pin will need a little adjustment to make it more sensitive for slow speed bike riding.

And lastly, here's a front view of how it looks at the moment. The only other major item I'm waiting on is the rear rack, after that, all thet'll be left to do is get the carb mounted and secure all the cables and wires.

oh, also I keep having a major problem with the supplied clutch cable crumpling up into a spongey disconfigured little knot. I've already trimmed it back once, readjusted the cable to have no tension when released, and it happened again while I was testing to see if the clutch was fully disengaging, so I ordered some new sturdy-looking brake cable to use for the clutch. Also got an extra one in case I have problems with the throttle cable being spongy too.

Another question - those round bits on the ends of cables - is there a tool set to put those on and where can I get one? If someone were to just tell me what the round bit and tool to put it on is, I'll research the rest myself. It would be much easier to secure all the cables if they were proper length, and so far they're all too long. In the case of the throttle, which has one round bit on each end, I can't trim down the line because then that round thing wont be there on one end. I also don't know if there's a proper tool to cut the cable, I just used side cutters on the clutch cable and managed to get that little silver crimp slid back over the end of it.

Please let me know if you have an answer or suggestion to anything posted here so far, thank you!

bluegoatwoods · Nov 2, 2013

Welcome aboard.

I'm a fan of posts with a lot of detail. But you actually did give us too much to work with. Not a big deal. But some of the stuff you've dealt with won't get covered in this thread simply because there was so much of it.

Anyway, it sure looks to me like you've got what I would call a 24 inch bike. That's just a bit small, but you've shown that it'll fit in your bike. Except for the intake manifold.

The offset manifold from some of the vendors should do the job for you with less risk than a home-made one. But if you trust your fabricating skills, then you might give it a try. I'm no expert, but the impression I get with intakes is 'the shorter, the better'.

Definitely read threads. They'll answer questions for you. Even some that you don't know you have yet.

But feel free to start new (and narrower) threads with questions that have been asked in the past. Some folks look down on this. But I say that some questions should be constantly 'refreshed' for the sake of the newbies.

Chain Driven · Nov 2, 2013

bluegoatwoods said:
Definitely read threads. They'll answer questions for you. Even some that you don't know you have yet.

I certainly read threads, and use the search too - I'm not trying to get out of that, just stating my specific problem. Other people have had carb fitment problems, but not on a bike like mine, so the threads I've read with those problems haven't covered what I should do with mine, since it is different. It gives me some idea (that's how I found the BoyGoFast manifold), but I haven't been able to draw any amount of certainty from it.

What I'm aiming for is for people who have done this enough to be "expert" or simply very knowledgeable to make an educated assessment of my particular build and give suggestions on what I need to do. I know such people are around. I also do as much research as I can myself before asking questions, and continue looking after asking too. But this is not something I do every day (its my first in fact), so there are some things that I have no direction for what path of research to take. For instance, I would surmise that there is a tool for crimping the round things on the ends of steel cable. But I don't know it's name, so I cant search for one. Thats my best example right now, but I would appreciate any help with all the questions I've asked so far. I don't ask something out of laziness, I ask because I don't know. I spent a long time looking for answers before even joining here. I'd rather not bother anyone with questions and just post about the build progress, but there are a few things I need direction with right now. If I ever started building these in numbers, I'd have a lot more "common sense" in this subject, but right now its not common sense for me. I can understand how a long time builder might be annoyed by some of the things I'm asking for that reason. Also please bear in mind my time is limited, so any answers are greatly appreciated. I could go on about why my time is limited but I'm sure you people don't want my life story. The simple story is, I'm just here to find answers, and appreciate all that are given. This stands true for anyone who reads this - although this response is primarily to bluegoat (and I would like to thank bluegoat for the reply), that doesn't mean anyone else can't read and reply to it.

Thanks to anyone who reads this and helps! :tiny:

Chain Driven · Nov 9, 2013

Greetings, silent internet peoples

I have taken the singular suggestion to get a carb adapter from the distributor I was originally considering. As you can see, this adapter puts the carb pretty far out and after a test of positioning myself as I would normally on this bike, the carb gets into my thigh pretty good. I suppose that happens to everyone who uses one of those? Good thing I (hopefully) won't be pedaling that much.

I've also added a fully adjustable rack and moved the running light to the tag plate on the back, and I think it looks quite nice.

And here is an updated picture of the bike:

I still need to replace the clutch cable, cut a hole in the seat cover for the brake light, and get the right and derailer more permanently mounted. I think that will be all before securing all the cables and doing my first start-up and test run.

Also, this will be my third time asking, so 3rd times the charm or 3 strikes I'm out? Anyways, what is the tool that crimps those little round bits on the ends of cables? I really need to shorten that throttle cable because its too long. The clutch cable wont be such a problem because it only has one metal bit, but the throttle cable has two, so I can't just cut it without having some way to put another metal bit back on. I don't know what the metal bits are called either. I would gladly search the forum for that but I have no keyword.

bluegoatwoods · Nov 9, 2013

I've got a suggestion for your throttle cable. My fix to that issue has worked out well for me.

But the Sun's not up yet and I've got to go to work soon. I should have no problem tomorrow snapping a photo and posting back here.

I don't have the name of the tool you're asking about either. But you might not need it after this.

KCvale · Nov 9, 2013

Chain Driven said:
Well, I guess I spoke too soon - I was promptly greeted in the introduction section but in this section it seems the original author of a post replies to their own topic as much as any suggestions or comments are given by others.

You certainly seem to like typing Chain Driven, welcome to the forum ;-}

You have a simple 2-stroke engine kit and they have been around for years.
Most any question you have can be expressed in a couple short sentences accompanied by an up to date close up pic of that part of the bike.

1) What should I do about mounting my carb? Will the BoyGoFast angled intake work, should I make my own from EMT (if so, how to make the flange?), or ??? [your suggestion]

Stop the train...

Chances are you just started off wrong and now trying to make everything else fit to the mistake.

From what I can tell from your laundry room pictures and tidbits in your novel long posts was you fit the engine to your own front motor mount?

Chances are you didn't start by making sure the back motor mount fit to your ~18° angled back seat post at 90° when that is step one and what effects how the carb and exhaust as well as the drive chain will fit on.

Tip 1:
Forget the front mount for now and get the rear engine mount securely mounted on the seat post as low as possible with no gaps in the mount or any filler junk.
THIS MOUNT TAKES ALL THE FORCE!

Go as low as you can go with the engine, but watch the chain ends for the best length with or without a tensioner to fit around the sprocket and clear back frame chain stays.

NOTE: You want to end end up with 2 'skinny' ends in adjacent sprocket notches so you can drop a Master Link in to connect the chain ends.

Tip2:
Since all the drive force resistance is being handled by the seat post all the front mount has to do is resist the left side pulling torque force and of course keep the engine from falling out ;-}

Just measure the front down tube diameter where you want to put the front engine mount and either buy a good front mount or just a muffler clamp that size and make your own steel plate to fit it up to the engines front mount bolt holes.

I can give you tips when I can see what you have.

What size is my bike and how can you tell? (this one might be generic but I haven't seen a clear answer)

US bike sizes are measured by the length of the frames seat post from the center of the bottom bracket (where the shaft the pedal arms connect) to the middle of the top bar (the middle of the bar where it hits the seat post, not the top of seat post itself).

Bicycle speedometers are said to fit 26~27 inch bikes.. if the bike is not measured by the tire size, that would seem to be grossly inaccurate

Correct, analog speedometers can very depending on wheel size but all I have used within a couple MPH on a typical 26" and I love them!

If you want dead accurate get a wired digital speedo and measure the exact circumference of the wheel on the outside of the tire in centimeters and enter that in to it.

I hope that is enough to get you going on the right track and do yourself a favor for more help...

Find yourself a bland background for detailed bike pics and unlike answers to complex questions, be like Sargent Friday on Dragnet, 'Just the Facts Mam' for what you need help with ;-}

Chain Driven · Nov 9, 2013

you fit the engine to your own front motor mount?

My first go round with this fitment problem I did just as you described - fit the rear engine mount as low as possible while being flush to the post and tightened it down there, then made a mount from pipe strap for the front mount. Lots of pictures in the colored text - those are links to larger sized pictures than what can be posted in a forum post, all up to date pictures as of the posting and keeping a more linear description.

NOTE: You want to end end up with 2 'skinny' ends in adjacent sprocket notches so you can drop a Master Link in to connect the chain ends.

I've initially done as you said for the chain, there was still a good bit of slack and I couldn't remove another link. I've read there are half-links for these chains but I don't know how chains are classified (for example [unrelated], I think some types of pipe are called "schedule" then a number, its proprietary jargon for pipes) so not knowing what to look for, I haven't been able to search for a half link.

I can give you tips when I can see what you have.

It is in my first post, but to save your eyes here it is again and here you can see how it was after I made the pipe strap mount. I don't think the motor can be any closer because the studs don't fit around the tube, even after bending them apart.

center of the bottom bracket (where the shaft the pedal arms connect) to the middle of the top bar

It appears to be 14" or 15" if I measured correctly? Sorry if I still don't have that right, please do correct me if I don't have the tape measure in the right place..

Correct, analog speedometers can very depending on wheel size

Could you let me know your rim inner diameter (I'm guessing your bike is "26")? That would give me an idea if my speedomoter would be reasonably accurate. I'm not really looking for spot-on accuracy, just something thats not way, way off.

I'm holding off on cable adjustments at the moment, eagerly waiting to hear about bluegoat's solution for adjusting cable lengths. But if anyone knows the name of that round bit cable crimping tool, I'd still like to know. Thanks for the responses :tiny:

IbedaYank · Nov 10, 2013

Chain Driven said:
My first go round with this fitment problem I did just as you described - fit the rear engine mount as low as possible while being flush to the post and tightened it down there, then made a mount from pipe strap for the front mount. Lots of pictures in the colored text - those are links to larger sized pictures than what can be posted in a forum post, all up to date pictures as of the posting and keeping a more linear description.

I've initially done as you said for the chain, there was still a good bit of slack and I couldn't remove another link. I've read there are half-links for these chains but I don't know how chains are classified (for example [unrelated], I think some types of pipe are called "schedule" then a number, its proprietary jargon for pipes) so not knowing what to look for, I haven't been able to search for a half link.

It is in my first post, but to save your eyes here it is again and here you can see how it was after I made the pipe strap mount. I don't think the motor can be any closer because the studs don't fit around the tube, even after bending them apart.

It appears to be 14" or 15" if I measured correctly? Sorry if I still don't have that right, please do correct me if I don't have the tape measure in the right place..

Could you let me know your rim inner diameter (I'm guessing your bike is "26")? That would give me an idea if my speedomoter would be reasonably accurate. I'm not really looking for spot-on accuracy, just something thats not way, way off.

I'm holding off on cable adjustments at the moment, eagerly waiting to hear about bluegoat's solution for adjusting cable lengths. But if anyone knows the name of that round bit cable crimping tool, I'd still like to know. Thanks for the responses :tiny:

ok... lets start with the pipestrap...no no no and NO.. make a proper mount or buy one

go around this forum and look at ALL the build keeping in mind what each person used and how they used it

throttle cable... learn to SOLDER as that is what is on the ends of the cable. This cable is nothing more then a bicycle brake cable... also serves as a clutch cable only thing differnt is the little glob of solder at the end going to the carb

Fabian · Nov 11, 2013

To get the bike running efficiently you need to get rid of the left hand side single speed drive system - honestly it's a complete waste of time.

My advise to get things operating reliably and with good usability.

1) Bike with front and rear disk brakes - absolutely essential
2) Proper set of integrated mirrors and indicators like the Winkku system - absolutely essential
3) Sick Bike Parts shift kit - absolutely essential and now available with optional left hand side and right hand side chain tensioners
4) Jaguar CDI - absolutely essential if the engine is to have a long and happy life
5) Rock Solid Engines reed valve intake and walbro carburettor - not essential but from a practical standpoint, it is an essential item.
6) CR Machine Manufacturing (medium compression) billet cylinder head - not essential but from a practical standpoint, it is an essential item.
7) Cylinder Head Temperature gauge and Exhaust Gas Temperature gauge - not essential but very handy to have.
8) Brake light - not essential by the law, but in reality it is an essential item when riding on the road.
9) Bicycle trailer - not essential but very handy for carting tools and spare parts if venturing on long distance rides, or rides where there is a chance for mechanical damage to occur.
10) Good set of high power front bicycle lights - essential
11) Centre mount bicycle stand - not essential but very convenient for lubricating the chain drive system, or for repairing flat tyres.
12) Thorn proof tubes with slime - essential if you do not want to repair flat tyres.

Bike Build and Some Questions

Chain Driven

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bluegoatwoods

Well-Known Member

Chain Driven

New Member

Chain Driven

New Member

bluegoatwoods

Well-Known Member

KCvale

In memory of KCvale 1959 - 2019

Chain Driven

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IbedaYank

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Fabian

Well-Known Member

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