new here and on my first build

MacZulu

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Jul 8, 2015
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hello, I joined here a few weeks ago and another forum. I have an active thread over there where I am receiving help and advice. and I thought it was time I should spend some time here going through the available info. where I'm at now

the bike is an electra townie ballon 7d, and I have a friend who will help me fab a mount for the pedal forward frame.
66cc with 40mm stroke. I have stripped the engine right down and have cleaned up the tranfers, exhaust and intake ports. matched ports and ramped piston head for transfers only. considering cooling troughs and holes. opened up exhaust and intake and matched gaskets.

I will be assembling the engine soon and then working on the mount fab.

anyways glad to be here, and will start combing through stickies and noob help threads.
 
Nice bike, $700, ouch.

Those Schwalbe Fat Frank 26" X 2.35" Balloon tires may be an issue.
Any tire over 2.128" and above is going to get some chain slap turning those pretty white tires black on the back left, if the chain will even fit around without outright rubbing.

A Jackshaft would solve that and give you a shifter but those forward cranks might be an issue for that as well.

Welcome to the forum and good luck with your build.
 
thanks KC, I like the bike for the seating position, and the flat foot at a stop design. as for the price my work provides a yearly budget for fitness equipment, education costs and things related to those areas. the bike is within the limit and the pretax price is reimbursed pretax on my pay. so it will cost me between 200 and 300CAD after all the tax and deductions.

ya the tires are 2.35". I was wondering about adding spacers to the sprocket clamping system to put the sprocket further from the tire?
the outer face of the rim is unpainted steel, and I guess kinda looks like a whitewall? it's not prominent enough in person to look like a whitewall and I hadn't had that impression myself. but that doesn't matter, I can't have the chain rubbing. and I hadn't really been thinking much about it lately, been busy with engine. thanks for the reminder, I guess worse case is I get a narrower tire until I have the shift kit.

there is a guy on youtube with a normal townie 7d with a shiftkit and torque convertor with a belt driving the right side, he has drilled two holes through the bikes sorta flat section at the bottom for the rear engine mount. I dont know if the shiftkit forced him to go that way, because I won't be drilling holes through my frame. I work with a guy who was a machinist and is happy to help, so all my fab work will go to him. I have a good idea about mounting, a local mb'er has a very nice simple and clean custom mount. it is aluminum, but I'll probably have to go with steel.
 
my work provides a yearly budget for fitness equipment, education costs and things related to those areas.
so it will cost me between 200 and 300CAD after all the tax and deductions.
Sweet ;-}

ya the tires are 2.35". I was wondering about adding spacers to the sprocket clamping system to put the sprocket further from the tire?
The back sprocket has to be lined up with the engine sprocket, and you can't move the engine out without making your own new offset engine mount.
That always gets dicey.

Just run a 2" rear or go with a jackshaft.
As for the wheel color, the pic I was looking at had entirely cream colored tires.

Coaster7Large_zpsfacd2062.jpg


Now there is something hard to keep clean with a 2-stroke.

there is a guy on youtube with a normal townie 7d with a shiftkit and torque convertor with a belt driving the right side.

A little 4-stroke and jackshaft kit, your frame has enough room for a big V-Twin hehehe.

Id spent the extra $200 and go with a SBP HD jackshaft.
Maybe even the Super HD freewheel if they have them in.

The real test of a freewheel is when you pedal start.
The pals have to withstand you literally standing up and force pedaling your engine to start it.

The more compression your engine has, the harder it is to start, thus the more force against the pals that under normal operation just ratchet free.
It also solves your back mount issue.
The front mount however will be an issue regardless.

Good luck with it and lets hope you didn't 'over mod' your engine to the point it won't run.
It happens.





As long as the bearing themselves are quality the HD
 
I'm going mount the sprocket on the back tire today and see if spacers are viable option. I suspect I will just get a 2" tire for now, as I don't know when I'll get the shift kit. Someone may sell me one, but if I go new it would be the set with the better bearing. the middle package I believe, first I need some runtime. as you say I may need a new case and/or jug first, I think I have been conservative in my shaping though.

I have read about the difficulty in bump starting a shift kit bike with high compression. so far I have had to replace crank to jug gasket, it's now thicker, lower compression. my ngk spark plug is longer than stock, increase compression. material removed from jug, crankcase and piston, lower compression. haven't done the jug on glass/sandpaper yet, but will, increase compression. as far as, replacement heads, I like jake's, fred's has been recommended, and bicycle motor works is a contender as well. but that can wait, I think shift kit is next up.

when I first got the bike and the motor bug, I had a strained back muscle and couldn't ride the bike. so I bought the engine and started working on it (with guidance) having the aim of "cleaning it up". my mods and work done are more aimed at smoothing the engine out and having fun learning/doing a new interest. although, cutting the muffler stinger down and drilling holes in the end cap is more of a torque thing. and of course I went deeper than expected, so I'm pushing on regardless because I have to see it through. the fred and gasbike videos give a certain confidence, and I'm all done with the work now. I just need to get a new crankcase gasket, my replacement set one had a tear. so tomorrow evening I hope to assemble, and then I can start measuring for the mount system.

this is the bike I'm working with, you can see the big flat spot along the bottom of the frame.

20150710_185223.jpg
 
ok she's running, but I have some clean up work to do. wires and paint mostly. one thing I will definitely do, when I do it again.
PUT THE FRIGG'N MAGNET IN RIGHT THE FIRST TIME. That being said, she's purring like a kitten so far. no wide open, but she is responsive at a twist. running 94 octane and lucas 2 stroke semi synthetic at 20:1

20150816_201130_resized.jpg

stuff
sbp twist throttle/kill switch
sbp spark cable
jnm sound dampeners (I have outer clutch cover dampener as well, just not on yet)
high flow air filter
sbp fuel filter
custom engine mount
replaced rear sprocket hardware with 7/16"s
replaced tensioners bolts with 3/8"s
replaced rear tire with 1.95"


what I did
reinforce gas tank posts with jb and quicksteel
milled head
cleaned up transfers
cleaned up intake/exhaust ports
matched ports
ramped the piston head towards the tranfers
cut muffler stinger down and drilled a few holes in the end cap
hole in muffler by port (for motocross sound fx)

I had alot of help from a local mb veteran, and some forum help. so fix exhaust situation (patch or replace), clean up the cables, and cdi set up. paint touch up, and this and that and a little something and ...
 
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running 94 octane and lucas 2 stroke semi synthetic at 20:1
Just some tips:
Octane:
I run premium for the most part too but not for the octane, all octane does is inhibit per-ignition in super high compression engines.
These are not.
I like the 'Premium' fuel because it usually has less Alcohol in it, nothing in a 2-stroke likes Alcohol.

The couple of tanks of 'break-in' oil are to encourage wear for the rings to seat in the cylinder.
By using any kind of synthetic you are retarding that initial wear.

I run the cheapest 2-stroke non-synth oil at 25:1 for a gallon, Then move to a good synth at 32:1, way more like 50-75: for oils like Amesoil.

The point is, oil don't combust, it dilutes you combustible gas.
The more oil in the gas, the less bang you get.
All the oil has do is lube the inside of the engine since it has no internal oil system.
 
Thanks KC. I was going to use non synth for break in, then I saw this article someone posted a link too.

http://motorbicycleracing.com/2-stroke-oils.html

for break in he says to use what you plan on using once it's broken in anyways, so that's why I'm running the semi synth. obviously I'm a noob so I have to lean on experience of others and it was an experienced mb'er whole posted the link for reference. it also means I bought a boost bottle hoping to smooth out the engine, I'll still try it out once I'm broken in and see what I think. I have a couple things I want to try once she's broken in, I have been happy with her so. I drove with little throttle for probably first hour of run time, I have eased into wot for a couple seconds and eased out lately. she hits a short patch of heavy vibes and then smooths out in the higher revs, everything is holding together as well.

the 94 octane is the only octane guaranteed to have no ethanol present at chevron. but I wont be an octane snob, just don't want the ethanol as you pointed out. Thanks for any and all pointers and tips.

Isithunzi (6 of 6).jpg

Isithunzi (5 of 6).jpg

looking for springer forks to fit 9 1/2" steer tube, monarchs are 7 3/8" I think. I still don't know my diameter. these guys seem to be my best option.

http://www.classic-cycle.de/en/Forks-and-Parts/Springer-Forks/

so on we go, but so far she's running well.
 
Thanks KC.
She hits a short patch of heavy vibes and then smooths out in the higher revs,
everything is holding together as well.

Thanks for any and all pointers and tips.

View attachment 58759
Looking over your build I have a couple tips:

Nice to see you have dual V-brakes, no MB is safe with just one brake.
I suggest you replace your dual brake levers for a singe 'dual pull' brake lever for $9.
http://www.sickbikeparts.com/catalo...ducts_id=41&osCsid=ohf2olmujitnvj11v8vh0vcjv6

I have been using that particular 'teeter-totter' dual pull for years on everything with a clutch and 2 hand brakes.

You need to remove a link from your drive chain.
A bicycle chain breaker won't do that #415 chain, but a good one will, Harbor Freight has a couple.

A dremmel or grinder will work as well, you just grind off the pin nubs on one side where you want to break it.

Note you want to end up with 2 'thin' ends for the Master link.

Last I suggest your give your custom engine mount the Pass/Fail test.

Firmly hold your top bar with one hand.
Firmly hold your cylinder head with your other hand.
Now try to push your engine back and forth in the frame.

I am not talking sissy nudges here, try as hard as you can to make the engine move.
If it moves AT ALL that is a Fail.

Your engine needs to be one with the bike, metal to metal, no 'dampening' junk in there.
If it's not it will start vibrating more making it worse to the point of catastrophic failure.

I can't make out the details of your back mount but just keep in mind that mount is going to have to handle 2.5+hp for thousands of miles if you build it right ;-}

Have fun, but take it from a guy with thousands of miles riding with city traffic...
Safe Up ;-}
 
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