Help with chain clearance for wide tires

GoldenMotor.com

crassius

Well-Known Member
Sep 30, 2012
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not sure about hub clamps - but for rag joints, one can dish the tire to the right, then trim the left cone-lock nut thinner and push whole axle to the left to re-center tire
 

BOYGOFAST

New Member
Sep 28, 2013
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Citrus Springs Fl.
a second sprocket will work best if you need to keep on sprocket mounted on the dust cap to center it provided the bike frame furnishes room for that and washers to space it
 

bluegoatwoods

Active Member
Jul 29, 2012
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Central Illinois
a second sprocket will work best if you need to keep on sprocket mounted on the dust cap to center it provided the bike frame furnishes room for that and washers to space it
I suppose that could give a bit more clearance. But it sounds like a risky idea to me.

Consider the strain these sprockets put on our spokes. Now you've given that drive train even a bit more leverage against the spokes.

This sounds like a last resort only. Even then I'd be reluctant.
 

KCvale

Well-Known Member
Feb 28, 2010
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Phoenix,AZ
You can't shim the front 10T out in the engine enough to matter.
If you have a fat back tire you need to remount the engine out to the left.

That is why it is usually best to jackshaft a fat tire, the engine can mount where it should.

A clamshell back sprocket will let you do lateral chain alignment at the back wheel.

a second sprocket will work best if you need to keep on sprocket mounted on the dust cap to center it provided the bike frame furnishes room for that and washers to space it
Just FYI, take everything this guys suggests with a cup, not a grain of salt.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
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Central Area of Texas
You can't shim the front 10T out in the engine enough to matter.
If you have a fat back tire you need to remount the engine out to the left.

That is why it is usually best to jackshaft a fat tire, the engine can mount where it should.

A clamshell back sprocket will let you do lateral chain alignment at the back wheel.



Just FYI, take everything this guys suggests with a cup, not a grain of salt.
Ditto...... on all points made.

I was hoping KC would ring in here on this since he has a lot of experience with fat tire bikes.

If I wanted a fat tire bike build I would more than likely go the shifter direction, but if you have a welder and the other tools and skills to make you up an offset mounting set up you can do a single speed, but you'll also need wider cranks also most likely.

I agree about suggestions by BOYGOFAST, he may have good intentions, but he has not even had one successful bike build to the best of our knowledge yet, so yes NOT to be mean or rude, but BOYGOFAST in most of our opinions has no business dealing out advice to others, but rather should be spending a good bit of time on the forum educating himself on the proper ways of doing things and then actually accomplishing some personal success with his own bikes before so blindly offering advice that it seems he just kinda randomly pulls out of the air....lol!!!

.duh.
 

Knuckledragger

New Member
Sep 18, 2014
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Milford Connecticut
LOL! Thanks for the advice guys. I have basically same bike in the photo I uploaded and it has the Maxxis Hookworms with no motor movement. The motor is exactly as mine is and I need like 1/2 inch of movement. I have tried to email Jake but I was a headache of a customer and he will not contact me back.
( I was a headache because I was pissed my NEW bike had bald rub spots on my tires, bent rims, wrong exhaust etc. but I'm the problem for complaining!!)
I know the Venice Motor Bikes probably can help if anyone can drop him a line for me.
 

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fatdaddy

New Member
May 4, 2011
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Dear Boygofast.
I am writing to ask you as politly as possible, while also trying Not to be rude. To PLEASE quit giving advice at least untill you have tried most of what you advise. If you have never tried something, how can you tell someone else to try it? Please put one together yourself first if just to understand what actually goes into putting one together. Because from what I've seen in EVERY ONE of your posts, you have no concept of what it actually takes.
Please read and LEARN from the valued members of this forum before giving any more advice. Yer gonna get somebody killed giving bad advice..
and please dont get mad, get Motor Bike educated.
Thanks for reading
fatdaddy.usflg
 

bluegoatwoods

Active Member
Jul 29, 2012
1,581
6
38
Central Illinois
Dear Boygofast.
I am writing to ask you as politly as possible, while also trying Not to be rude. To PLEASE quit giving advice at least untill you have tried most of what you advise.......
........Please read and LEARN from the valued members......
............dont get mad, get Motor Bike educated.
Thanks for reading
fatdaddy.usflg
hmmm......it's not easy to deliver a message like this without seeming harsh or confrontational.

But this did a pretty good job of it, it seems to me.

And best wishes to anyone who's here and trying to be helpful. But 'wild' posts don't really help a whole lot.
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
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Phoenix,AZ
I have basically same bike in the photo I uploaded and it has the Maxxis Hookworms with no motor movement.
This skull and crossbones?



I'm surprised that frame would even take 3" Hookworms.
Does your pedal chain clear those tires?

[/quote]The motor is exactly as mine is and I need like 1/2 inch of movement.[/quote]

I suggest you put a 3-speed back wheel on it and use a SickBikeParts jackshaft, the difference is staggering.

If not, well, you can:

Just run a 2.5" wide tire.

Fabricate off-set motor mounts and buy an $80 Sportsman hub adapter and run single speed.

Mount a plate to seat most for a shaft on 2 bearings with a dual ~12T sprockets on the left.
The inner sprocket goes to the engine, the outer sprocket goes to the back wheel and run single speed.

Other than that there isn't much you can do because you can't bend chain around a wheel.
 

cannonball2

Well-Known Member
Oct 28, 2010
3,682
221
63
Colonial Coast USA.
I had the same issue when building my 3speed transmission bike. I solved my problem by running a multispeed wheel from a MTB. I replaced the multi freewheel with a single speed. Then centered the axle in the hub. The multi wheel is dished to the right and has a very flat dish on the right offering additional clearance. This worked for me. Its kind of hard to see in the pics. The dish allowed the clearance of a double to the right chain line. The wheel sits maybe a 1/4" offset from center, but its not an issue. You can see there in good clearance at the tire in the last pic. There would be good clearance for Hookworms with a single chain line. My tires are 1.95s.
 

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KCvale

Well-Known Member
Feb 28, 2010
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Phoenix,AZ
Thanks KC . Do you mean a Nexus 3 speed hub? And a Jackshaft? Here is a orange version of my bike with 2.5" Hookworms.
Nice build.




Ya, 2.5" is about as fat as you can go without mods.

You could just jackshaft your 3" tire bike and use the single speed coaster brake wheel but for ~$130 you can put a new 3-speed wheel set on it and get the gear advantage.

Just ways of getting around fat tires, heck this Sun Crusher had 4" wide tires on 3.5" rims and though the bottom bracket was a challenge it worked like a champ and hauls ass.



That's an 'almost finished' pic as I can't find the good finished pics at the moment but sure a nice way to get drive chain around fat tires.
 
Nov 27, 2013
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earth
www.Frankenbikes.com
i have done several wide tire builds and chain vs. tire (vs. engine output shaft) clearance is always an issue.

i make a spacer, a disk with the same hole pattern as the chainwheel.

heres a link to more details. http://motorbicycling.com/showthread.php?t=52405

My chopper frames have a ton of wheel clearance, so i last tried a 3/4" spacer. i have made 1/4", 1/2" and 3/4" spacers

you will probably start to run into frame vs. chainwheel clearance

you "may" be able to cheat your chain outwards without offsetting the engine

I like wide tires!