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Old 03-12-2011, 12:13 PM   #16
south OP
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So, while all the rest of this (pretty straightforward) stuff was going on, one issue occupied the bulk of my time and efforts: brakes, and, in particular, the front brake. Quite simply, the front brake on the (pre-'08) KLR sucks; and I personally am tempted to go so far as to say it’s dangerously inadequate. Despite the bike's relatively light weight, the single rotor and single piston caliper just don't get the job done. From my very first ride on the bike I knew something had to be done to improve the front brake.

Of course, the standard first upgrade with virtually any bike is to install braided SS brake line(s); that I‘d be fitting braided lines to the KLR was a given, but my concern with the KLR was that it was noticeably running out of (front) brake before I was running out of lever. Once a certain (modest) level of braking force was achieved, no matter how much harder I squeezed the lever--d*mn near all the way to the 'bar--the front brake failed to generate *any* additional stopping force whatsoever; what I got with the lever half way to the 'bar was exactly what I kept getting the rest of the way to the 'bar. Sure, a braided SS line would firm up the lever and doubtless increase initial bite, but it was clear that the stock line was not the weak(est) link in the chain.

Some quick online research revealed the "next step" in upgrading the front brake was/is an oversize rotor kit, which includes a caliper relocation bracket. However, 1) a number of KLR owners voiced concerns re ground clearance issues (don't know how much of an actual problem that would be), and, 2) a little in-house comparison turned up the fact that the Kawi 250 (and early 500 Ninjas) utilized virtually the same size (single) front rotor and weighed about the same as the KLR, but had considerably better braking performance, so the rotor clearly wasn’t the weak(est) link in the chain, either. See where this is headed yet? (Almost) only one thing left…

And that brings things back to front-end swaps for a minute. The one undeniable benefit to fitting an upgraded donor front-end to the (pre-'08) KLR is the ready ability to gain a 2 piston front caliper. But then I'd already ruled out a front-end swap because of all the work/hassles involved.

So, back to the 250 Ninja(/500 Ninja). One immediate difference between the front brake on the littlest Ninja and that of the KLR: 2 piston caliper on the 250, single piston on the KLR. A less immediate difference was/is that the front brakes mount on opposite sides--the KLR on the left, the EX250 on the right. However, (more research) turned out that the caliper mounting bracket on the right-braked 250 was/is a universal fit--left or right--on other Kawi models equipped with dual front calipers/rotors, and, as it naturally follows, the same twin-pot Tokiko caliper found on the 250 was/is found in left- and right- versions on the dual front disc bikes. Possibilities are percolating…

A little back-and-forth (rough) measuring between the KLR and it's EX250 garage-mate, and it *looked* like a left-hand twin pot caliper bracket would bolt up: in addition to being a universal left- or right- fit, the twin pot caliper bracket has a total of 4 threaded mounting holes, only 2 of which are used in any given application, so it *looked* like I could get 2 of them to match up to the KLR fork bosses. Off to Ebay…

Where I sourced a 1988 ZX600R (with 16K claimed miles) left front caliper--pictured complete with mounting bracket, brake pads, and banjo bolt--from the fine folks at Pinwall Cycle. Given the going rate of old(er) calipers on Ebay, I wasn’t entirely overjoyed about the $35 total to get it to my door, but I didn’t want to play wait-and-see, and the thing was shown complete with the bracket and even a set of pads so I could at least try to make it work without having to lay out additional money for the mounting bracket and a set of pads that I ultimately might not be able to use. The plan hit a little hiccup when the caliper arrived sans bleeder screw, banjo bolt, and one brake pad--pieces that were clearly shown in the listing’s pic and essential for the caliper to be “ready to bolt on and go” as claimed. Shot off a quick email to Pinwall figuring that, as a large bike salvage yard, it was a slam dunk for them to scrounge the missing bits and drop them in the mail. But instead, they went ahead and just refunded my money. Fair enough, I now had a free caliper and bracket, the banjo bolt and bleed screw would swap over from the KLR’s original single piston caliper, and I could pull the brake pads from the 250 Ninja for test purposes. Back on track…

For only long enough to find that the holes on the 2 piston caliper bracket didn’t actually line up with the mounting bosses on the KLR’s fork. Further, the bracket took 10mm bolts; the KLR used 8mm, so the fork boss holes were undersized. Lastly, the bracket required more space than was available between the fork tube mounting bosses and the rotor--i.e., the bracket was too thick. Well, I guess that explains why I couldn't find any caliper swap how-to threads in the KLR forums. Now, all this didn’t mean it wasn’t going to happen, it just meant it was time for a think.

Clearly, I had to overcome some mounting issues and some spacing issues; fortunately, I had a mirror set-up on the 250 Ninja to provide needed reference points for proper caliper-to-rotor placement/alignment. And, I had(/have) everything I need(ed) to add metal, reshape metal, and take metal away--and the final bit was that now the pieces I had to work with/on were free , so I had nothing to lose that way. I was ready to start thrashing away.

And it was a thrash--I was working and re-working the thing on the fly as I progressively gained a full(er) understanding of exactly how the thing needed to fit based on what the thing needed to do and how it needed to do it. After-the-fact, the mods to the bracket are pretty straightforward, but working it all out took some trial and error.

First and foremost, altering the fork mount bosses was out of the question: I wanted to be able to re-mount the original caliper if necessary/desired; I didn't want to weaken them in any way, and I didn't want to introduce yet another variable into what was shaping up to be a bit of a tricky undertaking going in. Anyway, my first step was to cut the leading edge of the bracket down just so it would clear the fork tube when in rough position at the fork mounting bosses (unlike the intended applications for the bracket, the KLR fork bosses are both cast close to the fork tube itself; the bikes made to take the bracket have a lower boss that extends a fair bit further off the fork tube, so the leading edge of the bracket clears the fork tube no problem.



I was then able to roughly position the bracket on the fork with the wheel and rotor in place and have a real look-see on where everything needed to be. At this point I became aware of a few issues (mentioned previously):

None of the bolt holes were in the right place--in order for the caliper to be aligned properly with the swept area of the rotor, the lower hole actually needed to be off the front of the bracket in order to kick the bottom of the caliper back to compensate for the close-set lower mounting boss on the fork; conversely, the bracket's existing upper bolt hole positioned the top of the caliper too far back.

While the OEM bracket and the planned replacement unit were the same thickness (6mm), the 2 pot bracket had guide tabs for the outer pad which stuck out from the inner face of the bracket and contacted the rotor.

The original bracket/caliper assembly mounted with 8mm bolts; the 2 pot assembly mounted with 10mm bolts--which obviously wouldn't fit through the mounting bosses on the fork.

Last problem first: as mentioned, I'd already decided not to modify the original mounting bosses, so drilling them out (and possibly weakening them in the process) to accept 10mm bolts was not an option. So, the new bracket would have to be fitted with 8mm (threaded) mounting holes--which was just fine in one regard, since new mounting holes had to be made/located anyway. However, the idea of downsizing the original/intended mounting hardware of the more powerful caliper wasn't particularly pleasing/comforting. An immediate (partially) compensatory measure was/is to upgrade the 8mm mounting bolts to grade 12.9, but I still had some concerns.

Which were actually addressed when I moved on to the issue of the bracket thickness. Again, I didn't want to modify the fork bosses, so shaving them down to gain the necessary (2-3mm) clearance wasn't an option. After some thought, I hit upon the idea of "pocketing" (around) the mounting holes on the bracket--the bosses would fit into the pockets; the bracket would fit over/overlap the ends of the bosses; and the bracket would then be shifted over off the rotor to the same measurement as the depth of the pockets. Further, since the protruding brake pad guide tabs were the actual points of contact with the brake rotor--and not the entire inner face of the bracket--I was free to build up the areas of the inner face of the bracket surrounding the mounting holes--whatever thickness of material I removed from the outer face of the bracket to pocket the mounting holes and thus shift/clearance the bracket (guide tabs) away from the rotor, I could add a corresponding thickness of material (so long as it didn't extend past the protruding guide tabs--which it didn't) to the inner face of the bracket and thus regain strength and appropriate depth of the threaded bolt holes.

This solution had the added benefit of addressing my lingering concerns over fastener strength. By pocketing the fork mounting bosses into the outer face of the bracket, the bosses themselves would accept (shearing) load directly from the bracket; as long as the mounting bolts held the overlapping bracket/fork bosses together, much of their work was done.

So, OK, I now had a plan.

Dovetail, bevel, and multi-pass TIG weld some additional material (1/4" plate--only slightly thicker than the 6mm bracket, and that just gave me finish-grinding leeway) needed to create/locate the new lower mounting hole:





Start the process of welding up the bracket's original mounting and lightening holes, test-fit, and determine/mark locations for new mounting holes:

https://lh4.googleusercontent.com/_a...12/klr_198.jpg

Grind down welds, cut down/form bracket's new leading edge, drill and tap new mounting holes:

https://lh3.googleusercontent.com/_a...12/klr_202.jpg

Cut pockets:



Weld up the rest of the un-needed holes, drill a few (more modest) lightening holes--because of the specific mods to the bracket, I wanted to err on the side of more strength rather than less weight--powdercoat, and (thought I was) done:





The big issue once you start pumping heat into a work piece--as happens when welding--is that stuff starts to move around--warping, twisting, expanding/contracting, etc. So every time I welded up one of the existing holes, or added material on the back side of the bracket, or whatever, the thing would be slightly deformed in one way or another--the brake pads wouldn't fit on their bracket mounts and/or the caliper wouldn't mount properly on the bracket's slides, or if the stuff did fit, it would bind up, etc., and I'd have to take measurements and try to determine what dimension was out of spec, and then tweak the thing to fit the pads and caliper as it should. And I'd invariably fix one issue and screw up something else at the same time.

After the above pic of the "finished" bracket was taken and I mounted it on the bike for the first time--thinking I was home free--I found that the piston-side pad wouldn't fit properly. Took the thing off, made another lengthy round of adjustments, re-powdercoated and re-installed. Now the pads fit, but the brake seemed a little draggy.

At this point--sometime after midnight on a week night --I indulged in a little denial, told myself that maybe the (used) pads off the 250 Ninja just needed to "sort themselves out" with this new installation, and I decided to take the bike for a test ride. Compared to the original caliper's performance, the twin pot stopped the thing like a heart attack. And I'd held off on replacing the original brake line so I could get an accurate comparison between the two calipers. Sure the lever was still spongy, but a firm pull would slam the fender d*mn near onto the front tire (granted, the near oil-free, underdamped forks certainly contributed to the effect), and the bike stopped right NOW. I was so jazzed, all was forgiven, and I immediately decreed the result to be well worth the trouble.

Which was good, 'cause when I got back and put it back up on the front stand, the front wheel was as draggy as ever, and the rotor was a fair bit warmer than it should have been. And it wasn't any better when I checked it again the following afternoon.

After a fair bit of fiddling, I discovered that the caliper moved perfectly freely on the bracket right up until the mounting bolts were fully torqued to spec, at which point it all but locked solid. Obviously, there was an issue with the mounting points on the bracket--i.e., the pockets--and the bracket was being slightly deformed when fully tightened to the fork mounting bosses, mis-aligning the caliper slides and causing the caliper to bind. Now, while the faces of the bosses were (more or less precisely) machined, their circumferences were not--they were just left as cast--and were therefore not exactly perfect circles. Further, I'd powdercoated the pockets just like the rest of the caliper (save for the slides), and the coating had "webbed" up the sides a bit and certainly wasn't entirely uniform across the mounting face across the bottom of the pockets.

So, I went to work on the pockets: mill the pockets, install the bracket/caliper, torque to spec, check, fail, remove the caliper, and mill the pockets some more. Sometimes it was a little better; and sometimes it was a little worse, and the mounting bolts--bracket to fork--would even bind up as I was tightening/torquing them...until ultimately I stripped the threads in both bracket mounting holes.

Fine. Take the f*cking thing off, grind/mill off the powdercoat, weld up the d*mn stripped holes and the d*mn problematic pockets, grind the welds down, straighten the thing out, locate for new holes, drill, tap, and cut new (modified) pockets. Mount everything up while it's still all ugly...and the thing worked like a dream. Mounting bolts thread/tighten up cleanly; wheel spins free on the stand, stops immediately with the brake, and spins free again. Repeat the cycle a dozen times or so just to be sure (read: "just because I can't belive the frickin' thing is finally actually gonna work"), and it's time for another test ride. Got all the brake when I want it and none when I don't. Time to make things less ugly and mount it all back up for real, complete with braided line:







The stock brake line routing hangs the line from the handlebar brace-bar with a couple plastic clips--which were long gone. So, I made use of a 'bar pad I had from a set of Renthal 'bars I'd picked up for another project, and killed 2 birds with 1 stone: pad the 'bars and secure/route the front brake line:



So, not quite the slick, easy fab job I'd hoped for, but it seems that things have worked out in the end. Now on to some easier stuff.

south screwed with this post 03-12-2011 at 05:34 PM
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Old 03-12-2011, 12:21 PM   #17
south OP
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Rear brake line was simple enough to do. Routed the wiring for the brake light pressure switch up through the frame bracket which originally held the stock brake switch and along the downtube, and paired with the re-routed fuel tank vent hose (both visible in the 2nd pic located rearward of the kickstarter):





While I had the tank and seat off routing/connecting the brake switch wiring, I went ahead and performed a common KLR mod and installed a "T" (which I had lying around) in the gas tank vent hose--the standard hose out the bottom (prone to clogging when the bike is taken off-road) and a second vent hose tucked along between the airbox and frame rail. The hose looping over the battery/fuse area is the one (that gets) connected to the tank:



Also swapped out the footpeg and rear subframe bolts with grade 12.9 replacements--same exact bolts I'd used for the front caliper, so I'd just bought enough to go 'round at the time.

Another shot of the front caliper, now fitted with new pads; "test" pads returned to the 250 Ninja. The PO never balanced the front wheel/tire, something I discovered--and rectified--when I had it off for the caliper:



Better shot of the fork brace:



Sourced an OEM rear rack off ebay for $15 + $14 shipping. Had some knicks along one edge, but nothing a few layers of powdercoating wouldn't hide/fill. I wasn't digging the (cheap, painted, and scratched) silver finish anyway--thought (and still think) it looks much better in black.

Rack disassembled; section on the left beadblasted and ready for powdercoat, section on the right as received:



Coated and in the (no-more-cooking-parts-in-the-kitchen, dedicated parts-cooking, workshop) oven:



20 Minutes later:



Rack reassembled:



On the bike along with ebay'ed tool box fitted with new velcro-backed strap. New K&S brand, OEM-style clear-lense turnsignals still to come:


south screwed with this post 03-12-2011 at 05:46 PM
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Old 03-12-2011, 12:26 PM   #18
griffo1962
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none of your pictures are working.....
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Old 03-12-2011, 12:46 PM   #19
south OP
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At this point, I was able to get out on the thing and ride it (on the street) for a week or so, including slabbing out a work commute, and I decided to try and gain a bit more on the front brake.

The basic issue was that my preferred single-finger braking wasn't optimum with the KLR; with *just* the right hand/finger placement, I could manage a single finger full-pull on the lever without the lever getting back into my other fingers: full brake force, no finger interference. Braking with 2+ fingers worked great wherever my hand/fingers were on the grip, but that doesn't allow the same level of simultaneous throttle control that single-finger braking permits.

So, I acquired a(n inexpensive) master cylinder from a mid-90s ZX-6 off ebay, which sports a 5/8" bore--the next step up in bore size--and, of particular interest, the capacity to use an adjustable lever. It'd sit on the 'bar a little differently, but I figured it'd be worth a few bucks to try it out--the plan was to see if the 5/8" MC would give a little less lever movement and/or the ability to adjust/optimize the brake lever position, such that I could single-finger brake the thing as I'd like and am used to doing--without a negative effect on feel or overall brake performance, and, hopefully, perhaps even a further step up in performance.

Received and installed the MC and took it for a test spin. Couldn't be better; gave me exactly what I was looking for. With the (temporary) adjustable lever set at its maximum, I get 3/4"-1" of lever stroke for full brake (the same or perhaps fractionally less than with the stock MC), and the lever is well clear of my fingers still on the 'bar.

3 MCs. Stock KLR MC lower right, replacement ZX-6 MC upper right, and even newer plastic reservoir MC (taken from "inventory"--given to me by my neighbor along with some other odds/ends from a ZX-6R formerly drag raced by Tony Nicosia)--donor of the temporary (adjustable) brake lever. I considered using the plastic reservoir MC--since I already had it--for all of 2 seconds before disqualifying it as unsuited for rough duty:



MC installed:







Now just needed to source a black anodized lever, and that would be that.

And instead, I found some (short, "Superbike"-style) folding levers for a ZX6R which are presently enroute from the far side of the planet. In the meantime, I locally sourced a (used) corresponding ZX6R clutch perch (with one-handed adjuster) and lever and installed that in place of the KLR-only OEM clutch perch and lever; unlike the stock unit, the ZX6R perch will accept the on-its-way folding lever.

So, as of now, here it sits:






south screwed with this post 03-12-2011 at 05:53 PM
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Old 03-12-2011, 12:52 PM   #20
south OP
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Whoops, sorry about the (lack of) pics, guys. Didn't realize they'd block the links; I was just trying to save myself a whole bunch of work, especially since this site only takes one attachment per post. Lemme get to work on fixing.
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Old 03-12-2011, 05:56 PM   #21
south OP
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Alright, should be good--and if it's not, lemme know and I'll just forget it and bag the whole thread.
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Old 03-12-2011, 05:58 PM   #22
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There we go, we have pics!
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Old 03-12-2011, 06:08 PM   #23
south OP
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Quote:
Originally Posted by newcastleadam View Post
Cool beans. Might have bid against you on some Pinwall Cycle auctions (agree with your comment on 2004 model bikes, must be something about Ohio) .
...

Oh, I just finished a 2 pot caliper+relocation bracket+310mm rotor+14mm master cylinder conversion this morning from an eBay seller in Miami. Cost ~$250 to my door and the brake improvement is incredible. Just saying
If so, then thanks for driving the price up.

Despite the fabrication/fitment hassles, I'm quite happy with my $25 front brake upgrade (would've been $60 total without the Pinwall refund), even moreso upon hearing the $250 price tag on the kit, thanks. Out of curiosity, does the kit MC come with/allow for an adjustable lever?
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Old 03-12-2011, 06:09 PM   #24
south OP
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Quote:
Originally Posted by brucifer View Post
There we go, we have pics!
Thanks! Glad to hear I didn't just waste a bunch more time.
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Old 03-25-2011, 12:11 PM   #25
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Wow, south amazing writeup South. I enjoyed this whole thread. Your fabrication skills really came in handy here, and I'm glad you did so much experimenting with things. Looks like it was a fun project.
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Old 03-25-2011, 06:22 PM   #26
guns_equal_freedom
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Get an over sized rotor.

Nice project.
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Old 03-29-2011, 08:17 PM   #27
south OP
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Thanks, gents.

GEF--no oversize rotor needed; a 2 finger pull will pretty much stand the thing on its nose. I'm very happy with the present braking capability of the bike (and it doesn't hurt that I weigh in at 150lbs.)

Just received and installed my new levers--swapped out the stock KLR clutch perch for a ZX6R unit to match the MC and allow for the use of aftermarket adjustable, extendable, and folding levers:









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Old 01-26-2012, 06:45 PM   #28
south OP
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just to finish off

Last mod to the bike was to install a 3/4" (one-way) check valve to the crankcase breather to eliminate oil loss as the motor mists oil out the breather during normal operation. This mod has been so successful--bike hasn't lost a drop since installation over 8 months ago--that a similar set-up will go on my 250 Ninja commuter, which has always "processed" oil much like the KLR did: out the breather, into the airbox, then to the motor, and out the exhaust.

Instead of routing to the airbox (and interfering with my choke lever install), the plan is to run a hose to a protected/shielded area up under the seat; the valve generates a slight negative pressure in the crankcase when the motor is running, and although it seals tight at that time (i.e., when the engine is running), I want to avoid a possible scenario where the hose end is underwater and the bike stalls and the thing sucks water into the crankcase.

Valve:







Installed:

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Old 06-22-2012, 09:32 PM   #29
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Nice work. I envy the the lathe skills.
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Old 06-23-2012, 07:53 AM   #30
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I'm surprised I missed this when you originally posted it. But, better late to the party than never. Nice work, I like it a lot.
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