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Old 10-07-2013, 08:21 PM   #961
e28rusty
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hmmmm.. Does anybody have a set of the custom triples they would take measurements from? Or a set sitting around that they aren't planning on using?
I might try to make it with the ktm parts but I'll probably eventually do it right, I feel like I lack steering lock as it is..

My other question is about the brakes. I have 2 discs up front now, my new forks came with a 260mm disc and a master and caliper but no bracket. Am I looking at not enough brake force with the 260? I really don't want to spend the money on the big brake setup and I'm not sure it would work with my forks anyway (they are from a txc 400 I think). Should I just get the bracket for my caliper or do I need to try to go bigger?

I would also love dimensions for the wheel spacers if anyone could measure those, I made some but I'm not sure how tight everything should fit.
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Old 10-08-2013, 02:15 AM   #962
Ras Thurlo
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Quote:
Originally Posted by e28rusty View Post
hmmmm.. Does anybody have a set of the custom triples they would take measurements from?
have a look at the R-Dubb triples:

Quote:
Originally Posted by R-dubb View Post





Details:

I'll need to know if you plan to fit 43mm USD WP forks or 50mm Extremes.
190mm center to center matches KTM front wheels and is 2mm less than BMW.
The offset is 38mm (I succumbed to those who did not want more offset for fear of decreasing trail)
The large threaded holes w/ bolt in the lower clamp will serve as steering stops and are close to stock.
The four small threaded holes are the fender mount.
The stem bore will be 30mm (rather than the 28mm which is shown) and will take a KTM stem press fit.
A KTM stem and nut will fit if turned (0.5mm+/-) to accept BMW head bearings.
The top edges of the upper and lower clamp will have a 5mm fillet all around.
The upper clamp will have a raised handlebar boss designed for BRP big bar or 3/4" D-clamps or even better......
A BRP / Scotts submount as fit on the BRP triple clamp for a KTM RFS.
The submount puts the handle bar 60mm above the clamp which is already 25mm over stock.
This position allows Protapers to reach up to the stock bar height (varies with bar selection).
A Scotts damper can be bolted on with custom fitting of a weld on control stem (easy job).
The upper clamp will conflict with the late model PD or GS dash board.
It will not conflict with the fairing itself or the gas tank.
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Old 10-08-2013, 04:40 AM   #963
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Quote:
Originally Posted by e28rusty View Post
hmmmm.. Or a set sitting around that they aren't planning on using?
Ha! That's funny!!! I waited almost a year to buy some from HPM guy......you won't find a used set....no way. But, you can pop the DRZ triples straight onto the bike. Same stem size so bearings fit. Here's Beaters thread on his use of the DRZ forks and triples.
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Old 10-08-2013, 10:24 AM   #964
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Q for the KTM front end fanboys/girls...

Rather than machine up custom triples, why doesn't anybody just machine down the KTM stem from 29 to 28, cut it to length, add threads, buy a pair of 28/52 head bearings, and pop that KTM front end right into the airhead? Pushing out that stem and turning it down can be done by any machine shop anywhere, for maybe an hour or so of shoptime.

Seems a lot cheaper/easier than custom triples made from unobtanium.
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Old 10-08-2013, 10:26 AM   #965
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Quote:
Originally Posted by DiabloADV View Post
Q for the KTM front end fanboys/girls...

Rather than machine up custom triples, why doesn't anybody just machine down the KTM stem from 29 to 28, cut it to length, add threads, buy a pair of 28/52 head bearings, and pop that KTM front end right into the airhead?

All of that information is in this thread... the answer is you can, provided you also knock off the steering stop from the frame or knotch the lower triple


Also, need to measure the weight of the KTM front end... I did end up putting in 800cc's of 5wt fork oil into the legs so they are ready to go.

Here are my pictures of that arrangement and I didn't ever run these... I popped for custom triples instead




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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 10-10-2013, 03:53 PM   #966
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There's a set of 640 fork legs on ebay now for $111 OBO if anyone is looking...

http://www.ebay.com/itm/1999-99-KTM-...41bd0d&vxp=mtr

I'm tempted to pick these up for spare parts...
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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 10-11-2013, 12:17 AM   #967
Ras Thurlo
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Quote:
Originally Posted by DiabloADV View Post
Q for the KTM front end fanboys/girls...

Rather than machine up custom triples, why doesn't anybody just machine down the KTM stem from 29 to 28, cut it to length, add threads, buy a pair of 28/52 head bearings, and pop that KTM front end right into the airhead? Pushing out that stem and turning it down can be done by any machine shop anywhere, for maybe an hour or so of shoptime.

Seems a lot cheaper/easier than custom triples made from unobtanium.
the issue remains that with the KTM triples you lack the offset of the OEM geometry/custom triples.

For sure this will mean less steering angle (a bitch in either town or tight trails), possible issues with hitting your tank and/or frame and handling/geometry will not be ideal.

Dont get me wrong its rideable, but not ideal. While unobtainium triples are expensive, once you have gone to the cost+hassle of converting the old cow into a badass dirtbike you might as well finish the job properly

I am riding on KTM+Marzocchi triples on my bikes, but will likely go for the custom triples as soon as the mortgage comes through
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Old 10-11-2013, 12:26 AM   #968
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You guys have chosen the wrong front end.

It's a particular problem with KTM front end conversions. I have YZ KYB USD forks which have a 25mm offset & a different clamping mechanism. I don't have the steering clearance issues that you guys are experiencing.
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Box'a'bits screwed with this post 10-11-2013 at 01:36 PM
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Old 10-14-2013, 08:47 AM   #969
SOLO LOBO OP
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steel replacement axle spacers: once I installed these and took the axle nut up to 25 ft lbs the front end worked well with little hint of stiction....

MSR Wheel Spacer Kit 11-1086




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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 10-18-2013, 01:56 PM   #970
e28rusty
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Thanks Solo I needed those dimensions.

What do you guys think about brakes?

I was going to try to run the ktm caliper and 260mm rotor with the bmw master that is currently driving two rotors. Is there any chance this will work or do I need to spend more money? I do have the KTM master but I am hoping to avoid screwing with the throttle and switchgear. What have you guys done?
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Old 10-18-2013, 02:29 PM   #971
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Quote:
Originally Posted by e28rusty View Post
Thanks Solo I needed those dimensions.

What do you guys think about brakes?

I was going to try to run the ktm caliper and 260mm rotor with the bmw master that is currently driving two rotors. Is there any chance this will work or do I need to spend more money? I do have the KTM master but I am hoping to avoid screwing with the throttle and switchgear. What have you guys done?
Most BMW master cylinders are to big for the KTM calipers. The KTM master can be modified to fit the BMW switchgear.
To make that work you need to weld on the KTM master.
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Old 10-18-2013, 04:27 PM   #972
SOLO LOBO OP
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Quote:
Originally Posted by e28rusty View Post

I was going to try to run the ktm caliper and 260mm rotor with the bmw master that is currently driving two rotors. Is there any chance this will work or do I need to spend more money? I do have the KTM master but I am hoping to avoid screwing with the throttle and switchgear. What have you guys done?

Marcus Best was an early adopter of the R-Dubb triples and road around the world on his G/S with the 260mm rotor... he said he would have liked a larger rotor.

I am running the 300mm rotor from a KTM 640 (that goes with my forks as they are different) and that paired with the stock BMW 12mm master cylinder is quite good.

Prior to that I was running a 320mm aftermarket rotor with the 12mm MS and the stock BMW caliper... I think the BMW/KTM combination is as good
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Quote:
Originally Posted by Stagehand
your bike is suitably dirty. Well done.
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Old 10-18-2013, 05:12 PM   #973
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I'm running a 300mm EBC wave rotor and a KTM MC and caliper. Stops on a dime.

Only problem I'm having is that my steering head bearing preload keeps coming loose. I'll only ride 20 miles or so at a time and it's able to work its way REALLY loose in that time. How hard are the rest of you torquing everything?
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Airhead Wrangler screwed with this post 10-18-2013 at 05:19 PM
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Old 10-18-2013, 05:35 PM   #974
e28rusty
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Quote:
Originally Posted by Prutser View Post
Most BMW master cylinders are to big for the KTM calipers. The KTM master can be modified to fit the BMW switchgear.
To make that work you need to weld on the KTM master.
Do you have a picture of this?
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Old 10-18-2013, 05:52 PM   #975
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Quote:
Originally Posted by Airhead Wrangler View Post
I'm running a 300mm EBC wave rotor and a KTM MC and caliper. Stops on a dime.

Only problem I'm having is that my steering head bearing preload keeps coming loose. I'll only ride 20 miles or so at a time and it's able to work its way REALLY loose in that time. How hard are the rest of you torquing everything?
I had the same problem. Had to turn the stem down as the bearing would not slide and load in the race. Dunno what torque I used, but it was excessive....akin to 40 ft/lbs to press it in.....but after I turned the stem down I used around 20 on the stem bolt. 15ftlbs on the pinch bolts at the stem. I have yet to have them loosen since turning the stem.
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