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Unable to reply directly to this thread... http://katriders.com/vb/showthread.php?t=77783
So I was contacted by a member here who wanted to have this mod done and provided me the link for the mod to go by. Yesterday I received a package with 2 sets of adjusters in the mail... a bandit set, and a katana set.
So... First things first, I pulled out a swingarm and put it up on the work bench to measure and ensure things were going to work out right.
So from that a few quick measurements to consider...
While the axle slot is 47mm total length, the axle is 17mm... so the total adjustment range is (47-17=30mm).
A chain wears and increases in length (commonly referred to by people as "stretching" but it doesn't actually stretch, just wears...). The tolereance for this is generally 2.5% variance. You check for this by measuring center to center on a chain comparing the length. A 530 (or 525, 520) chain has links that are 5/8" center to center. So, some quick figuring since we know the avg kat sprocket tooth count on a pre 600 (shortest chain used on kats most often) is 14/47 with a 112 link chain. Wanting only to count links in a straight line, your looking at the chain being on half of each sprocket so... 7/24 (rounded up) then 7+24=31 links. 112-31 links = 81 links. Round down for even number get and / by 2 = aprox 40 chain lengths on top/bottom on a pre 600 kat. So... the adjustment range would be...
40 X 5/8" = new length of 25"
25"X 2.5% max wear variance = replace chain at 25.63".
Fyi... .625 = 5/8". .6299 = 16mm
So just for chain "stretch" alone you need 16mm adjustment. That does not include the nessasary adjustment to get the chain/wheel on and off. You need to be able to loosen the adjusters enough that the chain can be lifted off the sprocket. So that is why your looking at needing just at 2X the "stretch" tolerance for the adjusters at 30mm.
As a confirmation, here is a series of the katana adjuster inserted....
At max length with nut flush against adjuster plate...
Keeping the plate in place, moving the adjuster to the opposite end of the adjustment range...
And now confirmation... the measurement between the nut and plate = the expected 30mm adjustment range.
So I got started on cutting the stud off of the adjuster and getting set up to weld in a nut when I though to myself... this seems familiar. Then I remembered, I've done this before.
Look above and pull down the box of misc adjusters I have and surprise... a katana adjuster I had already modified when I did my original swingarm swap on my Kat.
So a quick mix of parts together and ... disappointment.
***I thought I had some pics to clearly illustrate the next point, but I'll come back and edit them in tonight. ***
Combining the bandit bolt/adjuster cap with a katana adjuster in this method leaves you a bit... short... in adjustability. Being that the entire point of these is for adjustment, that kinda presents a problem.
That's right... Looking in you can see the measurement comes out to maximum possible adjustment range with this setup is right at 20mm. That's 10mm short to start. You have to have the bolt threaded into the nut to start with so the measuring point of "adjustability" is between the bolt side closest to the axle holder and the axle holder in the center. As you can see here... the bolt will eventually hit that holder and stop!
Well... that presents an issue since we already know we need at least 16mm for the chain "stretch". 4mm left isn't going to be enough to get a new chain on and off the swingarm.
***I'll edit and post more pictures to clearly show just how that looks in the swingarm... ***
As pointed out in the mod thread above... the bandit adjuster internal part and the katana adjuster internal part have a big difference in measurement between the axle holder and the end where the nut is welded on to it.
I figured since limited adjustment was an issue with using the katana adjuster, I would consider using the bandit plate and swap out the axle holders in stead of swapping out the nuts.
So first a test. I put the bandit adjuster internal into the swingarm and checked the range of adjustment on it. There was plenty of thread to get the adjuster all the way forward, but when I tried to adjust it back... I ran into another issue. It just stopped well before the full range.
Maximum adjustment...
This is why....
So the bandit piece is so long in the rear section, they plate and that adjuster meet and but against each other before reaching the full adjustment range.
So again... back to limited adjustability. Now what to do.
After a bit of thinking I realized that if I was able to extend the katana internal adjuster length... or at least the threaded portion the bolt goes into, then I could increase the adjustment range.
That's where the idea for some T Nuts came in to play.
A T nut...
Back to the katana adjuster with the stud removed, I enlarged the hole further so that a T nut could be inserted through it. This in effect moved the first 5 threads I needed for the bolt to grab onto much further back towards the adjuster place. This thus gives a lot more adjustability for the katana adjuster.
I tweaked the length of the T Nut so that when it was all the way back at max adjustment, the end of the T Nut did not hit or would sit just flush with the plate. This ensured there was not going to be the same problem we had with the bandit internal hitting too soon.
At this point we are needing the maximum movement range possible, so the bolt needs to terminate at max length with right about 5-6 threads into the T Nut. The OEM bolts that come with the bandit adjusters are too long. So I shortened them down...
Modified one on the bottom, OEM on the top...
And then we have the end results....
With 5-6 threads of the bolt in the adjuster T Nut...
Showing that we have full range of movement before the T nut hits the adjuster plate...
Pulled out of the swingarm ...
Almost can see that it's threaded in well enough...
Then fully adjusted to the rear... using the bolt to pull it all the way back.
And finally, again what it looks like out of the swingarm... This pic shows that the bandit adjuster plates have a slight recess. Fortunately that gave us more room to get the max adjustment we needed.
The final touch was to make the T nuts a "locking" nut. This was simple enough to do. Using a chisel punch and a hammer I made the end of the T Nut where the bolt screws in first... slightly oval shaped. This makes it so the bolt will still screw in, but enough force/friction is holding it that it can't just vibrate loose or fall out.
Krey
So I was contacted by a member here who wanted to have this mod done and provided me the link for the mod to go by. Yesterday I received a package with 2 sets of adjusters in the mail... a bandit set, and a katana set.
So... First things first, I pulled out a swingarm and put it up on the work bench to measure and ensure things were going to work out right.
So from that a few quick measurements to consider...
While the axle slot is 47mm total length, the axle is 17mm... so the total adjustment range is (47-17=30mm).
A chain wears and increases in length (commonly referred to by people as "stretching" but it doesn't actually stretch, just wears...). The tolereance for this is generally 2.5% variance. You check for this by measuring center to center on a chain comparing the length. A 530 (or 525, 520) chain has links that are 5/8" center to center. So, some quick figuring since we know the avg kat sprocket tooth count on a pre 600 (shortest chain used on kats most often) is 14/47 with a 112 link chain. Wanting only to count links in a straight line, your looking at the chain being on half of each sprocket so... 7/24 (rounded up) then 7+24=31 links. 112-31 links = 81 links. Round down for even number get and / by 2 = aprox 40 chain lengths on top/bottom on a pre 600 kat. So... the adjustment range would be...
40 X 5/8" = new length of 25"
25"X 2.5% max wear variance = replace chain at 25.63".
Fyi... .625 = 5/8". .6299 = 16mm
So just for chain "stretch" alone you need 16mm adjustment. That does not include the nessasary adjustment to get the chain/wheel on and off. You need to be able to loosen the adjusters enough that the chain can be lifted off the sprocket. So that is why your looking at needing just at 2X the "stretch" tolerance for the adjusters at 30mm.
As a confirmation, here is a series of the katana adjuster inserted....
At max length with nut flush against adjuster plate...
Keeping the plate in place, moving the adjuster to the opposite end of the adjustment range...
And now confirmation... the measurement between the nut and plate = the expected 30mm adjustment range.
So I got started on cutting the stud off of the adjuster and getting set up to weld in a nut when I though to myself... this seems familiar. Then I remembered, I've done this before.
Look above and pull down the box of misc adjusters I have and surprise... a katana adjuster I had already modified when I did my original swingarm swap on my Kat.
So a quick mix of parts together and ... disappointment.
***I thought I had some pics to clearly illustrate the next point, but I'll come back and edit them in tonight. ***
Combining the bandit bolt/adjuster cap with a katana adjuster in this method leaves you a bit... short... in adjustability. Being that the entire point of these is for adjustment, that kinda presents a problem.
That's right... Looking in you can see the measurement comes out to maximum possible adjustment range with this setup is right at 20mm. That's 10mm short to start. You have to have the bolt threaded into the nut to start with so the measuring point of "adjustability" is between the bolt side closest to the axle holder and the axle holder in the center. As you can see here... the bolt will eventually hit that holder and stop!
Well... that presents an issue since we already know we need at least 16mm for the chain "stretch". 4mm left isn't going to be enough to get a new chain on and off the swingarm.
***I'll edit and post more pictures to clearly show just how that looks in the swingarm... ***
As pointed out in the mod thread above... the bandit adjuster internal part and the katana adjuster internal part have a big difference in measurement between the axle holder and the end where the nut is welded on to it.
I figured since limited adjustment was an issue with using the katana adjuster, I would consider using the bandit plate and swap out the axle holders in stead of swapping out the nuts.
So first a test. I put the bandit adjuster internal into the swingarm and checked the range of adjustment on it. There was plenty of thread to get the adjuster all the way forward, but when I tried to adjust it back... I ran into another issue. It just stopped well before the full range.
Maximum adjustment...
This is why....
So the bandit piece is so long in the rear section, they plate and that adjuster meet and but against each other before reaching the full adjustment range.
So again... back to limited adjustability. Now what to do.
After a bit of thinking I realized that if I was able to extend the katana internal adjuster length... or at least the threaded portion the bolt goes into, then I could increase the adjustment range.
That's where the idea for some T Nuts came in to play.
A T nut...
Back to the katana adjuster with the stud removed, I enlarged the hole further so that a T nut could be inserted through it. This in effect moved the first 5 threads I needed for the bolt to grab onto much further back towards the adjuster place. This thus gives a lot more adjustability for the katana adjuster.
I tweaked the length of the T Nut so that when it was all the way back at max adjustment, the end of the T Nut did not hit or would sit just flush with the plate. This ensured there was not going to be the same problem we had with the bandit internal hitting too soon.
At this point we are needing the maximum movement range possible, so the bolt needs to terminate at max length with right about 5-6 threads into the T Nut. The OEM bolts that come with the bandit adjusters are too long. So I shortened them down...
Modified one on the bottom, OEM on the top...
And then we have the end results....
With 5-6 threads of the bolt in the adjuster T Nut...
Showing that we have full range of movement before the T nut hits the adjuster plate...
Pulled out of the swingarm ...
Almost can see that it's threaded in well enough...
Then fully adjusted to the rear... using the bolt to pull it all the way back.
And finally, again what it looks like out of the swingarm... This pic shows that the bandit adjuster plates have a slight recess. Fortunately that gave us more room to get the max adjustment we needed.
The final touch was to make the T nuts a "locking" nut. This was simple enough to do. Using a chisel punch and a hammer I made the end of the T Nut where the bolt screws in first... slightly oval shaped. This makes it so the bolt will still screw in, but enough force/friction is holding it that it can't just vibrate loose or fall out.
Krey
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