Dirtmobile - A KTM 990 Build

[Stumpalump]

I like the white. I wound up with a black 950 because it was low mileage. After pulling the restriction out of the end of the Akropovic mufflers this thing flies! Roll the gas and by the time your ready to shift its doing a 100. Before it would rev out in the mid 80s in the same amount of time. I think it runs a lot cooler as well. It's really nothing like a dirt bike but it is real easy to ride and silky smooth. I also have the KTM plastic hard bags. They are double layer and you can put water or fuel in the cavity some how but I have not fooled with them yet.

 

[Stumpalump]

A Scott's stabilizer is also on my rig and yes it works well. I use a GPR 4 on my KTM 200 and the Scott's is better. If you go for a stabilizer then consider the Emig 20 degree triple clamps with stabilizer. These big ktms are super stabil hi way cruisers so the Emig will just add a lot of control off road without hurting the on road much. The stock geometry really sucks for turning in the gravel and will wash out. The Emig is similar to what KTM did on the 950 super enduro. If not then raise the forks in the stock tripple clamp to drop the front a few mm. A little makes a big difference when off road.

 

[Mechanical]

A Scott's stabilizer is also on my rig and yes it works well. I use a GTR 4 on my KTM 200 and the Scott's is better. If you go for a stabilizer then consider the Emig 20 degree triple clamps with stabilizer. These big ktms are super stabil hi way cruisers so the Emig will just add a lot of control off road without hurting the on road much. The stock geometry really sucks for turning in the gravel and will wash out. The Emig is similar to what KTM did on the 950 super enduro. If not then raise the forks in the stock tripple clamp to drop the front a few mm. A little makes a big difference when off road.

Thanks for the tip! I did notice that the bike scrubs fairly easily. I had just attributed it to the stock tires. When I get a good dirt tire on the front I'll have to start playing with the fork height.

 

[Stumpalump]

Thanks for the tip! I did notice that the bike scrubs fairly easily. I had just attributed it to the stock tires. When I get a good dirt tire on the front I'll have to start playing with the fork height.

That's great that you even notice what's going on! Most won't spend the time learning how to dial in a bike. They don't want to mess it up. Most will say that 20 mm clamps or raising the forks in the clamps adds stability. If fact you loose stability by making it turn better when making these kind of changes. My last set of new tires on a very dialed in KTM 200 had the front worn out before the rear. That's on a two stroke dirt bike that also had a top suspension tuner helping. A lot of guys run the original front for years but when you have it dialed to turn you can carve or slide that front like nothing else. You can see the likes of Ryan Villapoto on a 450. He is standing on the pegs comeing out of a turn with that front sliding more than the rear. You can see his front end slide 5 ft out of a turn compared to where it's pointed. That's confidence in a front end and that does not come off the showroom floor. I love sliding the front as well, it's just too bad I'm old, slow and scared everywhere else! Fwiw I hear the Adventure has weak front spring but the adjustments you get out of the factory Clickers are great. I love a soft front end so for now my suspension is staying stock. That says a lot because my suspension guy is my friend and neighbor who builds the endurocross and enduros bikes for Taylor Robert and Destry Abbott who are all employed by the Kawasaki factory team. I think Taylor just won the national title. Any way I'm just saying that the adventures suspension out of the box is darn good and has great adjustability built in. If it didn't then then I'd be the first guy to get it tuned.

 

[Mechanical]

That's great that you even notice what's going on! Most won't spend the time learning how to dial in a bike. They don't want to mess it up. Most will say that 20 mm clamps or raising the forks in the clamps adds stability. If fact you loose stability by making it turn better when making these kind of changes. My last set of new tires on a very dialed in KTM 200 had the front worn out before the rear. That's on a two stroke dirt bike that also had a top suspension tuner helping. A lot of guys run the original front for years but when you have it dialed to turn you can carve or slide that front like nothing else. You can see the likes of Ryan Villapoto on a 450. He is standing on the pegs comeing out of a turn with that front sliding more than the rear. You can see his front end slide 5 ft out of a turn compared to where it's pointed. That's confidence in a front end and that does not come off the showroom floor. I love sliding the front as well, it's just too bad I'm old, slow and scared everywhere else! Fwiw I hear the Adventure has weak front spring but the adjustments you get out of the factory Clickers are great. I love a soft front end so for now my suspension is staying stock. That says a lot because my suspension guy is my friend and neighbor who builds the endurocross and enduros bikes for Taylor Robert and Destry Abbott who are all employed by the Kawasaki factory team. I think Taylor just won the national title. Any way I'm just saying that the adventures suspension out of the box is darn good and has great adjustability built in. If it didn't then then I'd be the first guy to get it tuned.

Yeah, the stock suspension is amazing. I am always impressed with how stable the bike is. With good suspension and tons of power is is wayyy too easy to scream down a county road at 70 mph. I feel like suspension engineers for dual sport bikes have a really hard job, trying to cater to so many different riders. KTM has done as well as is possible to provide a very capable platform for a wide spectrum of riders, right off the showroom floor. That being said, you are right about the front end. Just today I bottomed it out twice while pushing the bike down some rougher two track. I still have a little adjustment in the compression damping in the forks, but the spring preload is turned up all the way and it still feels a little soft for someone my size/riding style. I still need to think about what I want to do over the winter. I may take everything off and send it to Superplush for a respring/revalve in the front end. I have only read positive reviews of their work, and I don't think I would mind having the bike sit 2" higher.

 

[Stumpalump]

Yeah, the stock suspension is amazing. I am always impressed with how stable the bike is. With good suspension and tons of power is is wayyy too easy to scream down a county road at 70 mph. I feel like suspension engineers for dual sport bikes have a really hard job, trying to cater to so many different riders. KTM has done as well as is possible to provide a very capable platform for a wide spectrum of riders, right off the showroom floor. That being said, you are right about the front end. Just today I bottomed it out twice while pushing the bike down some rougher two track. I still have a little adjustment in the compression damping in the forks, but the spring preload is turned up all the way and it still feels a little soft for someone my size/riding style. I still need to think about what I want to do over the winter. I may take everything off and send it to Superplush for a respring/revalve in the front end. I have only read positive reviews of their work, and I don't think I would mind having the bike sit 2" higher.

The bike is so big that it's easy to just sit or stand on it and plow into bumps with the front end. Even a good rider will do that on a heavy bike. The guy I bought mine from did. He had Woodys lace up a stronger front rim. I have the stock rim and it still looks new but the stock rim is not super strong. I think adding to the problem is the ability to actually stand up on such a big bike. I don't know how tall you are but I saw your risers. Bar position is criticle. I mark the center of the top clamp so I can adjust in 1/2 mm increments. I usually wind up with them rolled a half mm foward from center. Center would be even with the fork angle. With your riser follow the forks up and see if the bars are lined up with the forks. Those risers need to be set not straight up in the air and not following the fork but right in the middle. Hard to tell from your photo but I think that's about what you have it. OK, so now we are in the ball park of position and remember a mm makes a difference. This is the trick....Do not set the bars for a good seated position. Do not set the bars for a comply standing position. Set the bars for an agressive stance and you will be in the middle. With an agressive stance you can muscle the beast up and over obstacles without having to plow into them. Keep the Allen wrench in your pocket and move the bars a bunch of times or after every agressive encounter. That's a pro tip and if you do nothing else to a bike then do that. You will naturally attack everything hard in a perfect agressive stance saving your front end and becoming a better rider. It will still be tall enough to stand and good enough to sit. Most set the bars for standing. Don't do it. Try agressive and you will still be able to stand just fine. As far as Superplush...the stock valveing on all WP KTM bikes is great unless you get too far from the stock spring rate. It can be dialed in near perfect. So you will spend 1500 to get it raised when a properly function stock height bike will do fine. That's a lot of money to milk the last bit of suspension tuning out of it but that is the best money you can throw at any bike if you push it. Just be specific on how the bike is doing. A tuner is always best because you pay once but they tune till its perfect. You can be dumb like me and just say I'm fast as hell now but I crash more on the slow rocky stuff. They redo what they do and the bikes become a weapon in all conditions. Or maybe it's too soft on the big hits and G-outs after that adjustments and he may tell you to add 10cc of oil to reduce bottoming. Those guys rock!

 

[Mechanical]

The bike is so big that it's easy to just sit or stand on it and plow into bumps with the front end. Even a good rider will do that on a heavy bike. The guy I bought mine from did. He had Woodys lace up a stronger front rim. I have the stock rim and it still looks new but the stock rim is not super strong. I think adding to the problem is the ability to actually stand up on such a big bike. I don't know how tall you are but I saw your risers. Bar position is criticle. I mark the center of the top clamp so I can adjust in 1/2 mm increments. I usually wind up with them rolled a half mm foward from center. Center would be even with the fork angle. With your riser follow the forks up and see if the bars are lined up with the forks. Those risers need to be set not straight up in the air and not following the fork but right in the middle. Hard to tell from your photo but I think that's about what you have it. OK, so now we are in the ball park of position and remember a mm makes a difference. This is the trick....Do not set the bars for a good seated position. Do not set the bars for a comply standing position. Set the bars for an agressive stance and you will be in the middle. With an agressive stance you can muscle the beast up and over obstacles without having to plow into them. Keep the Allen wrench in your pocket and move the bars a bunch of times or after every agressive encounter. That's a pro tip and if you do nothing else to a bike then do that. You will naturally attack everything hard in a perfect agressive stance saving your front end and becoming a better rider. It will still be tall enough to stand and good enough to sit. Most set the bars for standing. Don't do it. Try agressive and you will still be able to stand just fine. As far as Superplush...the stock valveing on all WP KTM bikes is great unless you get too far from the stock spring rate. It can be dialed in near perfect. So you will spend 1500 to get it raised when a properly function stock height bike will do fine. That's a lot of money to milk the last bit of suspension tuning out of it but that is the best money you can throw at any bike if you push it. Just be specific on how the bike is doing. A tuner is always best because you pay once but they tune till its perfect. You can be dumb like me and just say I'm fast as hell now but I crash more on the slow rocky stuff. They redo what they do and the bikes become a weapon in all conditions. Or maybe it's too soft on the big hits and G-outs after that adjustments and he may tell you to add 10cc of oil to reduce bottoming. Those guys rock!

Thanks for the tip on the bar risers. I moved mine back a little bit and now they feel much better. I'm currently looking at a set of 20mm clamps which will work with a steering stabilizer.

 

[Mechanical]

Tires

Current Tires
Pirelli Scorpion Rally Tires - http://tinyurl.com/94pwfam

I just spooned on a set of Pirelli Scorpion Rally Tires. Good traction, good stability, I have really enjoyed them so far. I'll just have to see how long they last.

 

[Frank]

Pirelli has some amazing technology built in to tires and I believe it wiggles its way to the average consumer. Some very high end cars and motorcycles run Pirelli's O.E. for a reason!

 

[RHINO]

-Most of my riding will be on dirt, only sticking to highway/freeway when absolutely necessary.
-I want to do a lot of riding in Wyoming, Colorado and Nebraska. These are big, stretched out states, and require a big gas tank.
-I missed the fun of an all out "rip and shred" put-a-smile-on-your-face machine, and I wanted at least a little bit of this quality in my new vehicle.
-I wanted a capable machine I could grow into.
-Will

with those requirements i would not have picked any of the big bikes, i woulda done something more like a 690 or a TE630 with aftermarket tank(s). but, you picked a good second choice and your enjoying it, thats what its all about.

 

[Mechanical]

Pirelli has some amazing technology built in to tires and I believe it wiggles its way to the average consumer. Some very high end cars and motorcycles run Pirelli's O.E. for a reason!

Yeah, I have really liked the tires so far. It seems like the front is really popular with many people, but I don't see many using the rear. I'm sure the Dunlop 909 is a bit better tire for the rear, but at nearly half the price I had to give the Pirelli a try.

with those requirements i would not have picked any of the big bikes, i woulda done something more like a 690 or a TE630 with aftermarket tank(s). but, you picked a good second choice and your enjoying it, thats what its all about.

I was very close to buying a used KTM 690. Ultimately, I decided that I wanted something that could comfortably do long range 2up. That was kind of the deciding factor between a mid-sized and larger bike. I guess I should add it to my list. Letely I have been thinking about getting a smaller trails bike (sometimes I really miss my old XR200), something fun for singletrack and that my girlfriend can learn to ride on. I just need to stop lusting over this: bit.ly/FPls1s

--Lets take a ride on this little tangent. :Astrologist: Not really related to what you said, I just feel like ranting this morning --

I have really bought into the jack of all trades philosophy. For me, the key is to avoid building a vehicle to the point that becomes overly specialized. Maybe it's a little naive for motorcycles, but it seems like it is the driving force behind many of the Expo Tacomas. My Tacoma has made me a true believer in that: I can comfortably drive the truck down the interstate at 80mph to Moab, camp in the truck all week, do some moderately-tough trails, hit up a furniture store on the way home, load a couch in the back of the truck and drive home. I turn into a giddy schoolgirl after I pull onto the highway after a 100 miles of rough road, set the cruise control to 65, and the truck drives straight as an arrow. What a feat in modern engineering! The upshot: when I was buying a motorcycle I wanted to find something that has the same relative flexibility that my Tacoma has, with the addition of putting a ****-eating grin on my face. So far the 990 hasn't disappointed. I think if someone was going to own only one motorycle, and wanted a dirt focused dualsport which is capable of conquering 55% of all singletrack, highways, and anywhere in between (possibly even 2UP) the 990 is a really good choice.

 

[RHINO]

i agree with the rant and live it myself. love the tacoma platform.



now that you mention two up, that changes everything and the big bikes are on the menu. KTM is the dirtiest of them all right now, but i am really diggin the triumph 800xc. and now bmw is doing a new 800 that might be a little more dirty than the previous one. there is some potential competition out there for KTM's big twin, i like the mix.

 

[Mechanical]

now that you mention two up, that changes everything and the big bikes are on the menu.

I should have mentioned that up front. Honestly, the 800xc was the only bike I never sat on or took for a test ride. It seems like they have a pretty loyal following. I'm sure they are excellent bikes. The new BMW stats are looking really good. After owning the 990 I definitely know one thing: I will never buy a bigger bike.

 

[Mechanical]

Gearing

Current Gearing
KTM 950/990 45t Rear Sprocket - http://bit.ly/VDqhDR

I decided to gear the bike down a little bit. The 990 is geared pretty high from stock, and I would like to have a little more grunt below 5 mph. I am starting with the rear sprocket (45t) and I'll change the front if I need to gear it down more.



Stock Gearing:

17t/42t = 0.405

Current Gearing:

17t/45t = 0.378

Common gear ratios for the 950/990:

16t/42t = 0.381
17t/45t = 0.378
16t/45t = 0.356
15t/45t = 0.333

Installation is easy, just remember to use some blue loctight when re-installing the new sprocket. The stock chain will work with a 45t sprocket as long as you flip the axle alignment blocks 180 deg. See below:

Stock Configuration:




Inverted Configuration:



Voilà

 

[Mechanical]

Rear Rack

After my best efforts at setting the bike on fire by allowing items fall down onto the exhaust, I decided it was time to replace the postage stamp sized rear rack. I am fortunate enough to have access to a laser cutter at work. I drew a simple rack in Solidworks, exported the files, and had a buddy buzz it out on the laser.

I built the rack out of 1/4" 5052-h36 aluminum plate. The overall dimensions of the rack are 12" x 15". I wanted something that would work well with ratchet straps, bungee chords, and butterfly clips. I cut out a few large holes just to save weight, however, a Harley riding coworker thought they were cup holers. :elkgrin: I suppose they could work for that.

Model in Solidworks




After tapering the mounting holes and running a sander around the cut edges I mounted the rack on the bike.