Rear chain adjust

Post Reply
Posts: 29
Joined: Fri Sep 12, 2014 10:12 am

Rear chain adjust


Post by txpan49 » Mon Jun 19, 2006 2:06 pm

Post by txpan49 on Jan 1, 2006, 9:19pm

I looked through the archives and did not see much on rear chain adjustments. Would anyone care to comment please on your tips to get your rear wheel straight and chain adjusted? I have a 1950 wishbone by the way.

Post by 1950bobber on Jan 2, 2006, 2:47am

For the most accurate adjustment, at least in my 40 years of riding....I now use a device called the C.A.T. Laser chain adjustment tool. It boasts a 100% correct adjustment and takes seconds. You place this small laser directed device against the rear sprocket area and aim the laser beam up the chain right up to the tranny sprocket. You can see the laser beam lay on the chain and can adjust the axle adjustment bolts to what either side of the frame sets that laser beam on every link in the same spot right up to the tranny sprocket. Easy, Fast and Accurate. Cost's about $100...not cheap but extremely useful. Can be carried easily in your tool roll with the carry pouch approximately 4" X 2" and the laser device only 2" X 2". Hope that helps..
Jim in Seattle "1950 Bobber"

Post by panfreak on Jan 3, 2006, 5:52pm

Or you can use a straight edge under the bike to front tire. I set my front end straight ahead while on my lift, then lay a long piece of wood (anything straight will work) across the rear rim/ tire and align with front tire. Works for me, and it's free.

Post by 1950bobber on Jan 4, 2006, 3:27am

So Rammy...what do you do for a chain adjustment while on the road.....go to Home Depot and buy a 2X4?

Post by Cotten on Jan 4, 2006, 3:49am

Its hard getting down on my knees anymore, and it's always been hard to see if that 2X4 is really square against those round tires: lotsa slop.
My method isn't practical on the road, either.
(Alas, nor does it have whistle and bells and flashing lights.....)
But it is damn accurate, and fast, AND cheap!
A straight length of aluminum pipe or conduit can be quickly made into a trammel with two mirror clamps and pair of foot-long pieces of threaded rod. (Or anything else improviseable ...)
With the ends ground to points, the rods can be clamped to the pipe to make a very large caliper.
Setting the machine up straight with the front wheel "tracking", the rods can be easily adjusted to the center-to-center distance between the axles. Comparing to one side to the other instantly tells you if the axles are parallel or not.
Low tech rules. Or should, anyway.


Post by 1950bobber on Jan 4, 2006, 5:46am

With ALL due respect...who says low tech rules? That quite possibly could be "old" thinking settled upon before convenience and accuracy was available. Come on now, instruments improve all the time...does improvent and ease of use mean we should look for the low tech method...for that matter, break out your smallest increment ruler and measure your cylinder bore so you can fit up some pistons! No, I doubt that would would be wise. I've somewhat exagerated my point....I'm not suggesting we all go out and pay $100 for a laser aimed chain adjuster...but in the context of the question, the man wanted to know a good accurate method of lining up his back wheel and adjusting his chain and though he didn't specify it had to only be "in his workshop", I took the question to the most applicable scenario..that being both in the shop AND on the road. I use the C.A.T. laser tool both in the shop AND on the road, I live with only the most minute adjustment error..that being only as good as my eyes can correct...but if $100 breaks the bank..Man, we're all in the wrong past time...HD's, especially Pans ARE NOT CHEAP PLAY THINGS! To each their own...lets give the man with the question all the options...but "LOW TECH IS BEST" is slightly opinionated and has it's place! No hard feelings...just thinking out loud I guess!
Jim in Seattle "1950 Bobber"Re:

Post by 51Hog on Jan 4, 2006, 6:48am

Haven't thought about this for a while, but, I seem to remember aligning the rear wheel for two purposes:
1--to make the sprockets run true with the chains, and
2--to align the rear wheel to the front wheel--(so she don't run down the road like a crab)

If I understand the usage of the laser correctly, all it does is to help align the sprocket/wheel with the chain? If so:
This does nothing for the sprocket on the tranny.--
It also does nothing for the alignment of the two wheels.--

I start with the wheels:
Tools:- Chalk line
- Framing square
- Tape Measure
- Level
-Measure the exact width of the rubber on both tires, and record the dimensions.
-Chalk three lines on the floor that are longer than the bike.
a centerline, and a line on each side of the centerline that will represent both sides of your tires. (Using the dimensions that you recorded from the width of your tires.)
-Move your bike to the lines and block up vertical using a level.
Make sure that the tires are centered in the lines using the framing square to transfer the location of the sidewall to the outside lines on the floor. It must be done in the center(Front to rear) of both tires.
To check your front, Stand the square up against the sidewall at the front of the tire, and turn the handlebars until the bottom of the square is ligned up on the corresponding line.
Make sure that the center of the tire also stays on that line.
Do the same for the rear using the square at the rear of the tire.
Make sure that the centerline is maintained throughout the process.

----Then I go to the tranny,
----Then to the engine
----Then back to the tranny , then to the wheel again.
Sounds like a lot of work right--Yep--But once it is done, you just have to count turns on the screws when chain is adjusted the next time.

I don't like doing the "Caliper" method.
If the front wheel is turned even a slight bit, you end up with a parallelogram, and running down the road like a crab. (No offense Cotten)

Post by 1950bobber on Jan 4, 2006, 9:26am are DEAD ON! I believe your procedure is extremely important...and every Pan should be so fortunate. I take nothing away from your method. And....once you've done that.....barring you haven't changed anything such as wheels, relaced hubs, new tires, removed tranny's or motors for rebuilds and so forth....THEN the fast, easy rear wheel-tranny sprocket and chain alignment is all you should have to do periodically....except maybe chain maintenance/repair/replacement! As for adjusting the chain alignment by counting turns on the adjuster screws...GOOD LUCK...your a better man than me to remember how many turns and you STILL can't be absolutely sure the chain is running true!!!! Not to mention, adjuster screws are not, to my understanding, exactly equal that you can measure the exposed distance and be guaranteed the wheel is straight. Now you might say I'm full of shit....but I too have used most well known methods to get this job done. Can I measure my success? I'm not all that positive I didn't create some minute uneven wear on the tires...I sure could tell if I had front to rear wheel misalignment....Look I'm not getting any kickbacks on the sale of C.A.T. laser adjusters....all I'm saying is if you haven't tried one, do yourself a favor and speak from experience. It's fast and accurate....what's the basis of your disbelief? Skepticism? OK...I'm done...I know no one has said anything against my suggestion...I'm cool here...don't want to raise any ugly feelings among you great bunch of very knowledgeable guys. I respect you all and your opinions...just trying to impart a convenient alternative..nothing more...honest! finished...........
Jim in Seattle "1950 Bobber"

Post by Rammy on Jan 4, 2006, 1:16pm

Ya you know when you get it right when you can let go of the bars on straight road and the bike goes nice and straight without pulling to one side

Post by Mbskeam on Jan 5, 2006, 12:28am

the way I do mine is by taking a straight edge about 18"-20" long, pull the chain. then you fish the straight edge up into the sprockets , lay it on edge and see how it aligns with the trany sprocket, front side and then back side. adjust as needed.
once this is set any time I have to move the wheel back,I mark the adj. bolt and count the turns. seams to work fairly well.....

Post by panacea on Jan 14, 2006, 4:42am

I've always used that virticle rib the adjuster threads thru, measuring from the center of the axle to the center of the rib. Make both sides the same with about 5/8 movement at the tightest spot (rotating wheel to find the tightest spot.) has always worked for me!..MW

Post by Skip on Feb 6, 2006, 4:50pm

hell I just use my eyes...available at your local face and always there and ready... make sure the sprockets line up...start it and is not rocket science...for 21 years I have never done anything but that.

Post by 1950bobber on Feb 7, 2006, 4:24am

Now that's good advice! Do you work at a repair shop? Which one?
Jim in Seattle "1950 Bobber"

Posts: 53
Joined: Tue Mar 22, 2005 8:20 pm
Bikes: 48 Pan - Clone
Location: Ontario - Canada
Has thanked: 1 time

Re: Rear chain adjust


Post by Chobber69 » Fri Sep 10, 2010 8:26 pm

Am at the stage of my project, where the alignment issue comes into play. Great bantering going on here, can see some knowledgable souls in this thread...of 4+yrs past! Appreciate reaping the rewards; one thing I've learned...options exist! Thnx :-)

Posts: 3337
Joined: Sat Jun 26, 2010 1:54 pm
Bikes: 1958flh 1969sporty,had a knuckle but sold back to original owner
Location: NEW JERSEY
Has thanked: 195 times
Been thanked: 259 times

Re: Rear chain adjust


Post by 58flh » Mon Apr 25, 2011 1:26 pm

Whats-up men? I was just reading the posts & heard of this laser liner for rear sprocket & trans sprocket. $1 to $200 really? Check this one out my ol lady got me a laser for x-mas a few years ago.It cost $19.99,& was suppose to lay-out doors & windows right on the brick or sheetrock etc. it was a round unit with 4 adj. lasers on it! A real piece of garbage!!! ( I took one of the laser-pods off it & adapted it to a dial indicator magnetic mount! works great for rear sprocket to tranny drivegear. I can adj. it in less then a minite,& away you go!.) I gave another-one of the lasers to a good buddy of mine,& he made his adjuster out of a piece of alum. & a clothspin! Works great-I checked it against mine & mine on his they were both dead-on!!!. I just wanted to write this so alot of guys out there could save $$$!. You can buy shit laser products cheap. Then construct your own. Just remember this dont line everything with the front wheel!(I working to solve that using the lasermount-let you know how i made out.) Wheels-up Stay safe!

Post Reply

Return to “Chains & Belts”