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Discussion Starter #1
Just a general question - if you're doing custom wheel work, i.e. non-standard hubs, what do you guys use as spacer material? What works without a machine shop to make stuff for you?

What do you guys use for bushing material if you have a brake caliper carrier with a hole large than the axle you're trying to mount it on?

One of the things I'd like to do is get rid of the speedo gearbox on my current project - I intend, at some point, to replace it with a magnetic sensor. However, I've got this huge hole to seal, and of course there's the matter of the spacer to keep the wheel lined up right.

Any thoughts?
 

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I've only got a second but I'll see if I can quickly leak some of my mushy gray stuff out on the keyboard

spacers without a machinist.......

Local Hardware Store of good "jobber" type Autoparts place

Machine Bushings OR AN washers OR certain engine spacers off other dead motasiggles

Brake Caliper pivots....... trickier without a machinist and can you post several many pix of what you are trying to marry? Dimensions would be nice too......
 

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McMaster-Carr is your friend. They got thousands of various spacers and bushings.

I'm a big fan of Machine Bushings (washers) that Hack mentions...often hardened steel, quite flat and accurate in thickness.

Hack, here's one for you...what the heck are motorcycle electric starter motor sprockets made of? I was trying to weld one....was making a real mess. So much so I stopped and put a magnet on it to make sure it was ferous. Then heated it up with a propane torch and watched a thimble full of oil come out of the thing. A couple of heatings and quenchings and it was oil free enough to weld. Stange stuff....oil porous steel? Looks almost like a powdered metal product...they didn't have that back in the 60's did they?
JohnnyB
 

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I always save stupid shit like worn out bearings, aluminum bar ends etc. Basically any round or flat stock that I may be able to drill or cut into something else. Problem is, most of the time for something like an axle or brake stay/collar, it has to be fairly specific and I'm not happy with "close enough". With axle spacers the inner bearing races can work, assuming you need to replace one, keep the old one and remove the inner race, then it's just a matter of a washer or two to take up the remaining space on the axle. But then you have the gap between the seal and the bearing to think about...

FR
 

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Discussion Starter #5
Yeah, I haven't figured out how in heck I'm going to seal up the speedo gearbox end of the wheel. Might just leave it on there till I figure that out.

Hack - I've been sitting here daydreaming about how to wedge a disc brake rear end onto my bike but maintain a spoked rear wheel, at a reasonable cost (reasonable cost, that's the trick, see). Sure, there are CB750 rear ends with spokes and discs, but people get lots of money for those, fast.

I see a lot of dirtbike rear ends that look like just the ticket, except it looks like the axle hole on the carriers is bigger, so I'd have to figure out a way to put a bushing in there.

Naturally, my brain seized hold of my wallet before I did anything stupid on eBay - "IDIOT - dirtbikes have a 520 sprocket out back and you need 530!" Not to mention the tooth count/diameter of most dirtbike rear sprockets is considerably larger than my 450 sprocket.

This is a little longer-term than my immediate build finishing - it's going to be drum brake all the way for now. Yes, I know the CB450 has a good drum brake. It's the principle of the thing - I just like the looks (and the weight!) of disc brake setups.
 

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hmmm

my guess is that some spoked UJM disc brake rear wheels don't fetch big money and three to five of them sell on ebay each week

even with cush drives but your idea of big money for a rear wheel and my idea

may be worlds apart

sometimes I make as much as 20 or 30 bucks in just a week so I do tend to spend large

I'd also guess I snag them every time I can snipe them with the trick alloy wheels and not have to pay any more than 15 cents on the dollar....... I really like it when they have new tires on them for free

but regardless...... if having to purchase a sprocket means it's too expensive a project

may as well can the whole notion since you'll likely need some brake hoses made up as well

however, there are plenty of sprocket cross reference charts so that you could probably match something up on a 25 buck dennis kirk type sprocket and not have to spend 60-80 for a sprocket specialist unit

JB, I'd guess powdered metal as well but that would only be a guess

not sure how long it's been available but I know some of the really expensive powdered metals to be had today aren't porous at all

hard to say for sure what it truly is but your hunch makes sense

hit the next trashed one with a grinder and have a look see

what filler did you use? 309? 347? Nickle?
 

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quote:

Naturally, my brain seized hold of my wallet before I did anything stupid on eBay - "IDIOT - dirtbikes have a 520 sprocket out back and you need 530!" Not to mention the tooth count/diameter of most dirtbike rear sprockets is considerably larger than my 450 sprocket.
I don't believe there is any difference in the sprockets from 520 to 530 chain. I think it's all in the chain. Reason is, we ran a 520 dirt bike chain on my son's VFR for an emergency repair, got him home from Iowa. Ordered the correct new chain and sprockets, sure enough, it was 530 chain. We compared the old and new sprockets, identical. It's just heavier pins and links on the 530.

But to answer the problem at hand, as HackA has said, patience and some clever searching and sniping on ebay should get you a reasonably inexpensive rear wheel or hub assembly that would work....whether from a dirtbike or street bike. It's worth searching for flattrack wheels, they frequently use quick change rear hubs, which would be pretty trick on a caferacer.



FR
 

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Hack, actually no filler at all, the joint was such that I could just TIG up the small seam. I was joining it to some kind of mild steel I made a bushing out of.
JohnnyB
 

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Discussion Starter #9
Well, I guess I really could run a 520 rear sprocket and a 530 front sprocket, as long as I use a 530 chain:

from here:

*****************************************************************
The 5 represents 5/8" as the distance from one pin to the next.
The 3 represents 3/8" as the distance between the plates.
*****************************************************************

So yes, FR is right, I can do it.
 

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the 520 sprocket is 0.125" thinner than a 530 sprocket

if you don't think so

try running a 520 chain on a bike which has 530 sprockets

so how about some pix of the caliper and wheel stuff you want to marry?

I'll post up some pix of a drum brake early 70's sporty front wheel married to a CB750 honda fork set on custom mid 70's trees

later today anyhow
 

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borz,
Are you under the impression that you can use a 530 chain on a 520 sprocket? Yeah it will fit on the rear sprocket...but won't last very long. You don't want a chain wider than the sprocket, it will do all kinds of weird things....before destroying something...possibly you.
JohnnyB
 

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Discussion Starter #12
Hack, I agree completely with you - there's no way I could run a 520 chain anywhere I was using a 530 sprocket - but I might be able to use a 530 chain on a 520 sprocket. The pin-to-pin spacing is the same, which is the key part.

The only question in my mind is whether it's safe to do that or not, given the additional gap between the side plates on 530 vs. 520. Would I be at more risk of the chain jumping? Maybe I could take a 530 front sprocket and shave it down to 520.

I'd like to run hydraulic disc brakes out back, and aluminum spoked rims would be nice too - and you can get all these things pretty cheaply off dirtbikes, which also happen to often come with an 18" rear wheel. There are definitely streetbikes that have wheel/brake combinations that will work, but I'm trying to see if I have a wider variety of options than just one model year of C750's, or GL1000's, etc. Choice is good!
 

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Discussion Starter #13
Thanks, branson, that was what I needed to know. I like being not destroyed.
 

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the 520 is good for freeing up about 7 horses for high speed apps...... in addition to clearing a .250" wider tire if the chain run currently limits max tire width

and JB is spot on

the 530 chain on 520 sprockets will beat stuff up and fast
 

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just make sure that you are getting an 18" wheel if you are robbing a dirt bike. motocross models have 19" rears, while trail and cross country bikes have 18" wheels. 19" wheels came about in the late 80's when supercross was catching on, apparently a 19" wheel skims across whoop sections better. but your woods oriented bikes, your XR's, WR's, KLX's, RMX's, CRX's, EXC's, MXC's will have 18" hoops. as for the dirt track wheels, only vintage wheels are going to be 18" anything reasonably modern (80's and up) is going to be 19" because our dirt track tires are 19". a set of knock off wheels sure is nice though, i have a knock off on my racer and can change sprockets or just "flip the tire" in about 5 minutes. dont worry about your sprocket choice either, you can go all the way down to like a 36 on the rear for a motocross set up, just get ahold of sprocket specialists. if you need taller gearing than that, just start "adding" teeth to your front sprocket. a tooth on the front is worth 2.5 teeth on the rear though...so keep that in mind.
 

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show me some pix of "common" knock off wheels please, Sir
 

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ok pix of wheel adapt.......forgot to snap pix of the mock up spacers and such





chrome powder













imagine it is a cafe racer instead of a bopper
 

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jb

interesting topic... I am running a 420 chain on my 80cc. the countershaft sprocket is a 420, but the rear sprocket is 415 ( standard on rs 125s. do you think it will be an issue? i wasn't too worried about it since it is a 50cc(80).

matt
 

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Matt,
The 415 is about 1.5mm narrower than a 420. I gotta say I'm not sure, no the small engine doesn't make a lot of power...but I'd be worried about chain speed....they still go pretty fast. And if it's an RS sprocket it's probably pretty small in OD...which is going to make it behave even stranger I think.
I'd be leery about it....because if it screws up it's going to do it down the front straight when you are at max speed probably. That chain will squirm back and forth on the sprocket and if some weird harmonics start happening it will probably throw it right off.
JohnnyB
 
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