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Old 12-14-2012, 12:20 AM   #7711
warewolf
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Quote:
Originally Posted by mgorman View Post
The plus side, if the spring is cut, it automatically increases the rate since there are less coils to compress to move the same distance
Yes, because a coil spring is simply a conveniently-packaged lever. Shorten a lever, and we all know what happens, right? Stiffness increases.
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warewolf screwed with this post 12-16-2012 at 12:07 AM Reason: Speeling
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Old 12-14-2012, 05:33 AM   #7712
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Originally Posted by bmwktmbill View Post
One step heavier than OEM would get the front end up enough, I think.

I forget what the OEM wt. was in 2002 for the Adventure?
Anyone?
bill
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Old 12-14-2012, 07:24 AM   #7713
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Quote:
Originally Posted by warewolf View Post
I'm pretty light at 70kg but the 2005's 4.6s were too light for me, I swapped in 4.8s from a 950 and it is perfect! Totally transformed the front end having the correct springs.
70 KG was the target rider weight for the stock springs, you must ride pretty hard... The 2005 bike is only about 8 LBS heavier {most of it un-sprung} than the 03 so overall there should not be much difference in that respect...

My observations:
44s: blew through the travel much too easily and also bottomed often..
46s: Made best use of all the available travel without frequent bottoming...
48s: Spent most of the time in the top 1/3 of the stroke, rarely bottomed and even felt a bit harsh for everyday riding...
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Old 12-14-2012, 09:46 PM   #7714
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My observations:
44s: blew through the travel much too easily and also bottomed often..
46s: Made best use of all the available travel without frequent bottoming...
48s: Spent most of the time in the top 1/3 of the stroke, rarely bottomed and even felt a bit harsh for everyday riding...[/QUOTE]

Thanks for that Gunner and to those who offered their springs.
Guess I'll stick with what I have...with the ADV posted revalve the ride iis plush and does not bottom..
bill
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Old 12-15-2012, 12:39 AM   #7715
tileman
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Front rotor question.

Hi All.

I'm just sorting some parts on my new(used) 640. I had a motomaster disc not being used and I decided to swap it over. The disc OD is the same and the swap was easy.

BUT. Now the front is making a weird clicking noise when being wheeled around the shed after the swap. The original front disc was just over 4mm thick and the M/M is just under 5mm. Is the new disc just to wide?

[IMG][/IMG]

Has anyone else used such a disc? I got it with some other parts from a 950se. Motomaster doesn't list a disc for the 03 model. The metalgear site lists a option but it is only listed as 4mm thickness.

http://metalgear.com.au/mgear-brake-...ft-p-6772.html
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Old 12-15-2012, 01:35 AM   #7716
warewolf
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Quote:
Originally Posted by gunnerbuck View Post
you must ride pretty hard...
Maybe, maybe not. Aside from the poor handling, I just could not get decent sag numbers. Opposite of the rear, which is too stiff. What my suspension guru said was that all those guys that have disappeared off the top-level competitive circuit are now KTM test riders. Not only do those guys prefer a stiff rear and light front - because that is best when you have the throttle open all the time - but from a sales & marketing point of view, when you have a choice of two then generally it is better to bias the front light and the rear hard. Seems to stack up to me, with the caveat that having raced from the same pit as Chris Birch, seeing just how blindingly quick he came past me on the track, and the attitude he had the bike under brakes on a whooped-out downhill (basically back wheel at head height waving in the air near full-lock), I completely understood when he said "they are badly under-sprung at the front for quicker riders". So I dunno what sort of terrain KTM test riders are on, but Chris thinks they are soft at the front on the sort of terrain I ride on. Admittedly we were on two-stroke EXCs at the time, but the theory seems to hold.

Quote:
Originally Posted by gunnerbuck View Post
The 2005 bike is only about 8 LBS heavier {most of it un-sprung} than the 03 so overall there should not be much difference in that respect...
Not my bike There's 8lbs of unnecessary crap sitting in a box on my garage shelf.

To add my observations to yours:
44s: blew through the travel much too easily and also bottomed often..
Haven't tried.
46s: Made best use of all the available travel without frequent bottoming...
As per 44s above, and harsh because they moved too much so the damping kicked in hard.
48s: Spent most of the time in the top 1/3 of the stroke, rarely bottomed and even felt a bit harsh for everyday riding...
As per 46s above, and plush because the spring is supporting the bike and the damping matches it.

Dunno why that is so different between years?
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Old 12-15-2012, 01:37 AM   #7717
Low594
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Quote:
Originally Posted by tileman View Post
Hi All.

I'm just sorting some parts on my new(used) 640. I had a motomaster disc not being used and I decided to swap it over. The disc OD is the same and the swap was easy.

BUT. Now the front is making a weird clicking noise when being wheeled around the shed after the swap. The original front disc was just over 4mm thick and the M/M is just under 5mm. Is the new disc just to wide?

[IMG][/IMG]

Has anyone else used such a disc? I got it with some other parts from a 950se. Motomaster doesn't list a disc for the 03 model. The metalgear site lists a option but it is only listed as 4mm thickness.

http://metalgear.com.au/mgear-brake-...ft-p-6772.html
Can you shake the outer disc?? Looks like the new one is a floating disc, when the old is solid. If so you now have a floating caliper and a floating disc, which I suspect wont work well together!
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Old 12-15-2012, 04:03 AM   #7718
gunnerbuck
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Quote:
Originally Posted by warewolf View Post
Maybe, maybe not. Aside from the poor handling, I just could not get decent sag numbers. Opposite of the rear, which is too stiff. What my suspension guru said was that all those guys that have disappeared off the top-level competitive circuit are now KTM test riders. Not only do those guys prefer a stiff rear and light front - because that is best when you have the throttle open all the time - but from a sales & marketing point of view, when you have a choice of two then generally it is better to bias the front light and the rear hard. Seems to stack up to me, with the caveat that having raced from the same pit as Chris Birch, seeing just how blindingly quick he came past me on the track, and the attitude he had the bike under brakes on a whooped-out downhill (basically back wheel at head height waving in the air near full-lock), I completely understood when he said "they are badly under-sprung at the front for quicker riders". So I dunno what sort of terrain KTM test riders are on, but Chris thinks they are soft at the front on the sort of terrain I ride on. Admittedly we were on two-stroke EXCs at the time, but the theory seems to hold.

Not my bike There's 8lbs of unnecessary crap sitting in a box on my garage shelf.

To add my observations to yours:
44s: blew through the travel much too easily and also bottomed often..
Haven't tried.
46s: Made best use of all the available travel without frequent bottoming...
As per 44s above, and harsh because they moved too much so the damping kicked in hard.
48s: Spent most of the time in the top 1/3 of the stroke, rarely bottomed and even felt a bit harsh for everyday riding...
As per 46s above, and plush because the spring is supporting the bike and the damping matches it.

Dunno why that is so different between years?
I guess it is up to individual tastes, a lot of guys bump up to 50s and 52s on these bikes and some also go with revalving to get the results they desire... You do have a different set of forks on your bike from the 950s,but it's likely that the valving was changed to something similar to what the 03s run..

I don't race the bike and have stock damping up front, so ballpark is good enough for me... Out back I bumped the shock spring up one size stiffer on a revalved unit and it seems to match up pretty good with the front... With the stock valving the front end has a bit of chatter on the ripples when running light.. On the flip side, I do find is that my suspension gives the smoothest most comfortable ride when I'm loaded up for travel and that chatter felt on the ripples is much less prevalent...
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Old 12-15-2012, 04:05 AM   #7719
tileman
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Quote:
Originally Posted by Low594 View Post
Can you shake the outer disc?? Looks like the new one is a floating disc, when the old is solid. If so you now have a floating caliper and a floating disc, which I suspect wont work well together!
What I didn't know!!!!! Thanks, maybe I'll have to put the old disc back.
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Old 12-15-2012, 11:36 AM   #7720
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Quote:
Originally Posted by tileman View Post
What I didn't know!!!!! Thanks, maybe I'll have to put the old disc back.
It does look pretty cool! And it could be that it is just designed as a non-floating 2-piece rotor. I've seen them, but all of them were cheap materials, think Bling-Bling. Definitely warrants a closer look and maybe contacting the manufacturer. The pic seemed to have a part number!
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Old 12-15-2012, 03:37 PM   #7721
gunnerbuck
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Originally Posted by tileman View Post
What I didn't know!!!!! Thanks, maybe I'll have to put the old disc back.
That disk should work on your application unless the 2pc disk coupler rivet/washers touch the pads when you spin the wheel or hit the fork leg... I see no other reason why it would not work and I see many of these kind of 2pc disks listed to fit the 640A and E models... I measured a new spare 640 A front disk I have on hand and it is 5mm thick and the caliper piston/pads will open up far enough to fit it without binding....

Make sure your pins on the caliper to bracket are well lubed so the caliper will slide back and forth with relative ease to eliminate any binding... Make sure the fluid reservoir has enough room for the fluid to back into it when you push the piston back in to the cylinder, otherwise the pads may not fully relax their hold on the disk at rest...
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Old 12-15-2012, 03:59 PM   #7722
tileman
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Quote:
Originally Posted by gunnerbuck View Post
That disk should work on your application unless the 2pc disk coupler rivet/washers touch the pads when you spin the wheel or hit the fork leg... I see no other reason why it would not work and I see many of these kind of 2pc disks listed to fit the 640A and E models... I measured a new spare 640 A front disk I have on hand and it is 5mm thick and the caliper piston/pads will open up far enough to fit it without binding....

Make sure your pins on the caliper to bracket are well lubed so the caliper will slide back and forth with relative ease to eliminate any binding... Make sure the fluid reservoir has enough room for the fluid to back into it when you push the piston back in to the cylinder, otherwise the pads may not fully relax their hold on the disk at rest...
Just had a fellow member come round and pick up a fan I was selling and he pointed out the potential problem. You are correct the coupler rivet/washers on the disc are contacting the calliper mount. Should have picked up on it first when I fitted it, my bad.

A simple grind of the back of the caliper bracket will fix it but I don't know if anyone else has done this. It would only be a mm or so to fix.

Thoughts?
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Old 12-15-2012, 04:19 PM   #7723
gunnerbuck
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Quote:
Originally Posted by tileman View Post
Just had a fellow member come round and pick up a fan I was selling and he pointed out the potential problem. You are correct the coupler rivet/washers on the disc are contacting the calliper mount. Should have picked up on it first when I fitted it, my bad.

A simple grind of the back of the caliper bracket will fix it but I don't know if anyone else has done this. It would only be a mm or so to fix.

Thoughts?
If it is a very small amount of material that should be no problem, a flat file works great for gently removing the material...

I take a file to the rear caliper at regular intervals to square up the pad holding fingers so the pads fit true to the caliper... I removed a substantial amount of material to extend the service life without issue before I tossed it in favor of a new one...
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Old 12-16-2012, 03:29 AM   #7724
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Quote:
Originally Posted by tileman View Post
Just had a fellow member come round and pick up a fan I was selling and he pointed out the potential problem. You are correct the coupler rivet/washers on the disc are contacting the calliper mount. Should have picked up on it first when I fitted it, my bad.

A simple grind of the back of the caliper bracket will fix it but I don't know if anyone else has done this. It would only be a mm or so to fix.

Thoughts?
It should be ok tileman. The KTM disk is also a semi-floating disk and the one you have should be semi floating. Full floating disks are not present any more, mainly due to the noise they were doing. The rivets, on the new one, have spring washers in them,
In any case modifiyng the caliper in that area will not cause any problems but make sure you are gentle with it and if you have a thin disc cutter, use that. If the modification was near the bolts then it may have been a problem...

Let us know how it goes and take some photos
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Old 12-16-2012, 03:54 AM   #7725
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Also let us know if the new rotor gets rid of the squeal with the stock one.
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