Author Topic: My new chopper. A real "back in the day" survivor.  (Read 62042 times)

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Offline 754

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Re: My new chopper. A real "back in the day" survivor.
« Reply #50 on: June 02, 2013, 10:57:57 AM »
To really see what the apes would look like, try to line them up with thelegs of the springer, ie s sorta straight line..
Maker of the WELDLESS 750 Frame Kit
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My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline Stev-o

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Re: My new chopper. A real "back in the day" survivor.
« Reply #51 on: June 02, 2013, 11:00:12 AM »
Still thinking Z bars would look great, Jag.  Hard to found cheap ones though.
$90 here.....

http://punkchoppers.com/ZERO-Z-BAR-METRIC-7-8-BAR-ZEROZMETRIC.htm
'74 "Big Bang" Honda 750K [836].....'76 Honda 550F.....K3 Park Racer!......and a Bomber!............plus plus plus.........

Offline jaguar

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Re: My new chopper. A real "back in the day" survivor.
« Reply #52 on: June 02, 2013, 11:02:24 AM »
To really see what the apes would look like, try to line them up with thelegs of the springer, ie s sorta straight line..

To fit on the bike the apes had to be pushed way far forward.  Like 30* forward

Offline mjc477

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Re: My new chopper. A real "back in the day" survivor.
« Reply #53 on: June 02, 2013, 12:08:54 PM »
Love the old chopper

I love the old genuine choppers and cafes they just have something else about them

Have you thought about straight bars

I have an old BSA ( sorry for soiling this fine forum ) that has got straits on and it is very comfortable to ride......even the seat is better than it looks?

Offline jaguar

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Re: My new chopper. A real "back in the day" survivor.
« Reply #54 on: June 02, 2013, 01:12:10 PM »
Straight might work.
The drags had to much pull back.

Nice bsa!

I know what you mean about the old stuff.  I just love it.
Kinda funny the clubmans feel so nice...I HATE clubmans on cafe bikes.


Offline mjc477

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Re: My new chopper. A real "back in the day" survivor.
« Reply #55 on: June 02, 2013, 01:21:39 PM »
Yeah I know what you mean about clubman bars

At least with straights you can just try with any pipe you have kicking around?...for length and comfort

The ones on the bsa do In fact have a little pull back on them and I do have a riser bracket somewhere but with that fitted it looks less sleek.....I like it low.......

Offline jaguar

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Re: My new chopper. A real "back in the day" survivor.
« Reply #56 on: June 02, 2013, 02:18:16 PM »
Yeah I much prefer the low look to a bike.
I might try a broom stick tomorrow when I'm in the shop

Offline mjc477

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Re: My new chopper. A real "back in the day" survivor.
« Reply #57 on: June 03, 2013, 10:27:30 AM »
Good idea
If you can't find one
I'll see if the mother in law will lend you hers?.?.?

Offline jaguar

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Re: My new chopper. A real "back in the day" survivor.
« Reply #58 on: June 03, 2013, 01:09:13 PM »
Well put some time into the bike today.
-got the wiring all but finished.
-steering head bearings installed.
-bars and controls mounted.

Had an issue with the brake stay though...
Couldn't help but notice that when the brake is applied the force effects the suspension movement.  At best it licks everything from moving, at worst it causes the fork to bind in the full extended position.  I know it's not much of an actual brake, butthuscant be right.





What do you guys think?  Can't actually be right?

Steering bearings came out extra broken


Using one as a kill switch and the other for a horn button



Amal repro levers


Almost done with the controls




Offline Sprocketwerx

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Re: My new chopper. A real "back in the day" survivor.
« Reply #59 on: June 05, 2013, 06:28:34 PM »
Whatever the pic in the ad shows, those links need to be flipped.

Rake and trail works the same for any bike.
A line straight through the steering axis to the ground, mark that spot.
Next drop a plumbob from the axle centerline and mark that spot.
The distance from the axle mark and the steering axis mark is "trail".
Axle should be behind the steering axis, thus the term "trail"
Negative trail (when the axle is in front of the steering axis) is dangerous and should be avoided.
Think about a caster on a grocery cart. it always follows the vertical steering axis.
On a car rake and trail combine for the caster part of alignment, camber being the tilt of the wheel in or out.

On a sportbike, rake is very steep and trail is around an inch, resulting in quick steering.
Most choppers have generous rake and trail numbers of 3-5" are generally acceptable.
These aren't road racers although some of us ride 'em like they were.
Most are set up for long distance high speed stability, so quick steering isn't really a priority.

There are ways to bring trail more into "handling mode" and that's have new rockers built with the axle in the proper positon, be it more forward, or up or both.

The rear leg looks a little short, causing the unloaded bind, is there a spacer under the top tree above the bearings? Could be a longer stem from a different bike, Lots of mixing and matching back in the day, hell today still for that matter...lol


As for the brake, you are linked to the right spot, but the wrong angle.
The stay should be in front of the forks in a pull configuration. You have it in a push mode so it's making suspension work where it doesn't need to.
I run mine on the right side with no problem, the mechanism is not directional, but I've always seen them on the right side.


I have the same hub with a 16" on my 750 chop, and they anchored the brake to the rocker, so when I apply front brakes the front rises. It's not correct, but I have a lot of fun on cruise nights poppin' the brake and bouncing the springer off the ground. Kinda synch up the brakes with the bounce.

Bike looks cool and once you get the forks working right ya might be suprised how easy they are to ride.
A wise man once said... build it how you want it, then learn to ride it like you own it ;)

Dan "Sprocket" Harris
Sprocketwerx Motorsports

Offline jaguar

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Re: My new chopper. A real "back in the day" survivor.
« Reply #60 on: June 05, 2013, 07:31:47 PM »
I think more of the issue is that the springs are not set up correctly causing the bike to sit funny.  Also when I sit on the bike the lower link is parallel with the ground, so that should solve the trail issue.

Ill swap the link to the other side and see how it works.
I was told the stay should remain parallel with the lower link, and use hyme joints so it pivots correctly.

Offline heffay

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Re: My new chopper. A real "back in the day" survivor.
« Reply #61 on: June 05, 2013, 08:30:13 PM »
The death trap chopper thing is real, but many other things often get involved... suicide shift, no front brakes because they can never make it work right, etc... but now that you say the link is horizontal when you're on the bike that is relieving.  I've ridden several choppers, the first was my babysitter's older son's bicycle when I was about 7 or 8.  Talk about not being able to keep the front wheel up!  Any shift of weight from side to side and the wheel would flop over.  It had about 5 feet of forks and the turning radius of an old lady in a Buick. 

The next one I rode while working at Town & Country Motorsports in Chandler, evil, evil store, when we were considering taking it in on trade.  It was a slightly cool, but mostly dumb, CB350 twin that made a lot of noise and was also way too long for my bike stand!  Trying to get it in line to get on the stand was a 20 point turn in the shop.  It handled pretty well from 15mph on up.  Turning at the stoplight and low speeds were pretty terrifying though.  I was the only one willing to give it a whirl.  Memories of that childhood bike ride came flooding back quickly.



I dig the bike.
The awful red tank is gone, check.
The grips are perfect.
I think drag bars or some sort of very low bend bars might be the way to go. 
Outstanding survivor!
Today: '73 cb350f, '96 Ducati 900 Supersport
Past Rides: '72 tc125, '94 cbr600f2, '76 rd400, '89 ex500, '93 KTM-125exc, '92 zx7r, '93 Banshee, '83 ATC250R, 77/75 cb400f

Offline Retro Rocket

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Re: My new chopper. A real "back in the day" survivor.
« Reply #62 on: June 05, 2013, 09:00:07 PM »
Whatever the pic in the ad shows, those links need to be flipped.

Rake and trail works the same for any bike.
A line straight through the steering axis to the ground, mark that spot.
Next drop a plumbob from the axle centerline and mark that spot.
The distance from the axle mark and the steering axis mark is "trail".
Axle should be behind the steering axis, thus the term "trail"
Negative trail (when the axle is in front of the steering axis) is dangerous and should be avoided.
Think about a caster on a grocery cart. it always follows the vertical steering axis.
On a car rake and trail combine for the caster part of alignment, camber being the tilt of the wheel in or out.

On a sportbike, rake is very steep and trail is around an inch, resulting in quick steering.
Most choppers have generous rake and trail numbers of 3-5" are generally acceptable.
These aren't road racers although some of us ride 'em like they were.
Most are set up for long distance high speed stability, so quick steering isn't really a priority.

There are ways to bring trail more into "handling mode" and that's have new rockers built with the axle in the proper positon, be it more forward, or up or both.

The rear leg looks a little short, causing the unloaded bind, is there a spacer under the top tree above the bearings? Could be a longer stem from a different bike, Lots of mixing and matching back in the day, hell today still for that matter...lol


As for the brake, you are linked to the right spot, but the wrong angle.
The stay should be in front of the forks in a pull configuration. You have it in a push mode so it's making suspension work where it doesn't need to.
I run mine on the right side with no problem, the mechanism is not directional, but I've always seen them on the right side.


I have the same hub with a 16" on my 750 chop, and they anchored the brake to the rocker, so when I apply front brakes the front rises. It's not correct, but I have a lot of fun on cruise nights poppin' the brake and bouncing the springer off the ground. Kinda synch up the brakes with the bounce.

Bike looks cool and once you get the forks working right ya might be suprised how easy they are to ride.
A wise man once said... build it how you want it, then learn to ride it like you own it ;)

I agree with what you are saying but your sportbike trail numbers are way out, 05-08 GSXR1000 have 95-98mm trail which is closer to the 4 inch mark {100mm}, 1 inch {25mm} would make for a very nervous ride. Remember, its all relative to rake, a bike with 4 inches of trail and 26 degree rake will feel different to a bike with 30 degrees of rake and 4 inches of trail..... ;)
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Offline jaguar

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Re: My new chopper. A real "back in the day" survivor.
« Reply #63 on: June 05, 2013, 09:03:38 PM »
Yeah I didn't like the red tank.

I forgot I need to do something about the gearing.
Right now it's geared for like a million miles per hour.
Needs a larger rear sprocket at least.

Waiting to hear back from cycle X about making me a set of 550 pipes.
Battery was ordered.
Next is to tune the bike up and make sure the oil leak isn't a big deal.

Offline Stev-o

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Offline jaguar

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Re: My new chopper. A real "back in the day" survivor.
« Reply #65 on: June 06, 2013, 07:34:31 AM »
I'm running 7/8 bars.
But might buy them just to try.

Offline Sprocketwerx

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Re: My new chopper. A real "back in the day" survivor.
« Reply #66 on: June 06, 2013, 08:46:37 AM »
My bad on the sportbike trail numbers, I'm a chopper guy. :D

Main point is choppers aren't "one size it's all" so for a good handling chop, ya need to do the homework, work out the geometry, and sometimes that means moving the axle position.
Flipping the rockers and lowering the bike will also change the effective rake (de-raked) just a little bit which would also reduce some trail.

One thing that would help is seeing pics with you on it. Like you said, loaded makes a difference, and that 550 lightweight leaves it looking like there's no load at all.
Dan "Sprocket" Harris
Sprocketwerx Motorsports

Offline yeahyo

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Re: My new chopper. A real "back in the day" survivor.
« Reply #67 on: June 06, 2013, 09:43:22 AM »
+1 on the link on the springer to be flipped over. thats probally why the front brake locks the linkage

Offline jaguar

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Re: My new chopper. A real "back in the day" survivor.
« Reply #68 on: June 06, 2013, 11:17:05 AM »
The front brake would lock the linkage no mater what way the link was.
The arc of rotation for the brak stay and axle are very different right now.
Why would jammer sell the front end pictured and as smelled like I have it?
I understand that things need to be adjusted some times.
But I know it sits level when I sit on the bike, and I also know that that the springs are not 100% correct.


Offline Sprocketwerx

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Re: My new chopper. A real "back in the day" survivor.
« Reply #69 on: June 07, 2013, 12:17:20 PM »
That bung might be intended for a caliper stay, I dunno.
Again the "one size fits all" theory that doesn't always work well in practice.
Putting the link in a pull position will allow more rocker movement than in push mode, and I just don't like putting a flat bar in compression  for a brake stay. Even the stock Honda rear stay is formed with a stiffening rib to stop it from folding up in compression.

The link should be as close to parallel to the rocker, and the same length as the rocker from rear leg hole to axle hole, forming a parallelogram... that leaves adding a threaded bung in the right place on the rear leg, closer to the pivot as the correct solution for that brake hub. In push as he has it, the link is near 90* from the rocker, in pull it's not perfect, but much closer than perpendicular.
Dan "Sprocket" Harris
Sprocketwerx Motorsports

Offline Sprocketwerx

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Re: My new chopper. A real "back in the day" survivor.
« Reply #70 on: June 07, 2013, 12:26:50 PM »
One other thing about the brake stay... Both ends must be bushed so the link can pivot with suspension travel. Looks like yours is bolted solid.
Dan "Sprocket" Harris
Sprocketwerx Motorsports

Offline 754

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Re: My new chopper. A real "back in the day" survivor.
« Reply #71 on: June 07, 2013, 03:12:23 PM »
Your brake stay may be mounted wrong. It looks like the backing plate is PUSHING into the flat bar, it should be. Ahead of the axle so it is PULLING..  Slight possibility if it was applied moving backwards, that it flexed and turned back,but I doubt it.. Any small drum bike wheel will stop better than that one.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline jaguar

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Re: My new chopper. A real "back in the day" survivor.
« Reply #72 on: June 07, 2013, 04:23:29 PM »
One other thing about the brake stay... Both ends must be bushed so the link can pivot with suspension travel. Looks like yours is bolted solid.

True on both points.
Will be changing that

Offline jaguar

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Re: My new chopper. A real "back in the day" survivor.
« Reply #73 on: June 07, 2013, 04:25:22 PM »
Your brake stay may be mounted wrong. It looks like the backing plate is PUSHING into the flat bar, it should be. Ahead of the axle so it is PULLING..  Slight possibility if it was applied moving backwards, that it flexed and turned back,but I doubt it.. Any small drum bike wheel will stop better than that one.

I'm not expecting to do stoppies, but don't want a death trap.
Will swap so the link pulls and see if that's better.
But I think the comments about the stay being parallel to the link are correct,
Not sure how to do that yet.

Offline Sprocketwerx

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Re: My new chopper. A real "back in the day" survivor.
« Reply #74 on: June 08, 2013, 09:38:21 AM »
measure from the axle centerline to the anchor point on the brake plate. That is the distance the stay needs to mount above the rear leg pivot.
Measure the rocker from the rear leg pivot to the axle hole. That is the length of link you need.

Simple to draw and use a compass to show the arc that both links need to follow.
I went to a drag race suspension seminar about 5 years ago, and the first thing the instructor said (regarding ANY vehicle suspension) was "think of it like a glorified swingset". It's just not that complicated.
Create a cartoon in your head (or on paper) that visually describes the motions and limits of the links. Seeing it simplified geometry wise is easier than following verbal "instructions"

I don't post this stuff to be a knowitall, I ride choppers almost exclusively (and build them) and see a lot of cobbled junk that makes the rest of us look bad. I'd rather pass on how to build a safe ride so ya don't need a deathwish to enjoy a chopper.
Next week I leave for a few thousand miles towing a camper behind my chopper. Same brakes as you got here and a drum out back. If I didn't trust my brakes, I wouldn't tow through the mountains of West Virginia and the Carolinas.
Dan "Sprocket" Harris
Sprocketwerx Motorsports