Noob bought a 2006 KTM 450 EXC

[Repp]

Hey guys,

I'm a Mechanical Engineering student at Ga. Tech in Atlanta. I got tired of riding the bus and decided to buy a bicycle thinking it would be good for my health. I rode the bike 5 days.... The commute is about 2 miles. Many people ride scooters here so I shopped around online and decided to join the crowd. I found a nice 50cc scooter and took it out for a test drive. Immediately, I felt my testicles shrink, testosterone levels decrease to that of a boy in diapers and saw my masculinity start to dissipate before my very eyes. It was a traumatizing experience. Long story short, I found out you could ride dirt bikes on the road. I have owned many dirt bikes back home. The last 3 were 250 2 strokes. 

I bought the above bike 3 days ago (pics in profile). It was old, fairly cheap for KTM, and in good mechanical condition from what I have messed with so far. Front wheel has a slight axial displacement I don't like so I ordered front and rear bearings. Brakes good, frame good, engine noises good, no leaks, fluids good. I dont have a torque wrench here so that's an unknown. The suspension was set for a 200 lb guy before me and I'm 190.  Compression... well.. relative to my 250's, it's very strong and pulls for days.  I'm satisfied until I get home and have access to my shop. I have downloaded the owners manual, service manual, took driver test and got a license, got insurance (progressive full coverage 18$ per month), ordered oils, filters, spoke tool, rear spring tool, and a helmet. I have not driven it since I want to check valves, change oil, re-torque stuff,  and fix front bearings. Anything else yal see I should do?

Funny story: I met the guy with the bike in a very nice manicured suburb. I was thinking "I'm going to show this city boy how to really ride a dirt bike. I checked all the brakes (most important before showing your ass on a dirt bike) and checked everything I could with visual/touch inspection. I also gave him the full amount in cash in case i potato. I told him i was going to let it warm up and ride it very hard to make sure everything was mechanically up to my standards. Then.... well you know the rest. To my surprise, the 4 stroke is strong, very strong. In fact, I had difficulty knowing when to shift because it never quits pulling. It was my first experience on a big 4 stroke. I always laughed at them on my wore out 1k-1.5k   2 stroke on the track back home because it was the rich kids from town with the new 4 strokes, new trucks, custom air-conditioned trailers, matching gear, name brand everything, racing numbers on everything they own including the dog. They rode like molasses on Christmas day. They must have been Tweeting/Instagramming instead of giving that bike hell. Anyways, that set up my predisposition to 4 strokes. lol well....I can say now, they are definitely a contender but my heart will always be with the 2 stroke. I even miss the smell.

Thx for reading my post guys. I hope to contribute whatever I can. I have not ridden in about 7 years and It did feel awesome! Feel free to comment on things to check, common problems, common misconceptions.

 

[S.O.A.N.Z]

IMO - the best 4 stroke motor KTM has produced - RFS

Just rebuilt mine from ground up - 03 450 sx

 

[cobra46]

Nice bike.

I also grew on 250 2t bikes.  Back when I grew up in the 80's only old men rode thumpers.  After many years away from the sport I wanted a plated dirt bike.  I bought an '05 525 and have been very happy.  Granted I'm not going to win any races on a motocross track but it is still a very capable dirt bike.

The bad news is that since these are dirt bikes, their street manners are not very good.  You can help this by balancing the tires.  You should consider gearing up if you'll be riding at highway speeds.  I'm running 14/48 which is great on single track but revs pretty high on the freeway.  You may consider getting some less aggressive knobbies.  Those will wear out in a hurry on pavement.

One word of advice, be super careful with that kickstand.  KTM kickstands are not very strong.  Over the years I made a couple bandaid repairs to my stock one and it still never worked to my satisfaction.  I finally bit the bullet and installed a Pro Moto Billet one.  The are pricey but high quality.

Care to share what you paid?  Here in California that bike would fetch north of $4k

[KTMfinrider]

The little I know about older kmt four strokes that year of 450 rfs should be very reliable machine. 

[wakesetter5477]

Congrats on the bike.  If you're riding that thing primarily on the street, start looking for some used supermoto wheels.  Sooo much fun!!

[Repp]

Yup, you are right about the flimsy kickstand. I got under the bike this morning and found a crack on the small mounting tab. It actually fell off during disassembly. I will mig weld it back and add a gusset since the original design did not have much horizontal support. It looks to be a little off 90 degrees. I think I will use solidworks to make sure the geometry is correct and make the gusset and new tab. School let’s me use the water jet cutter so that will be easy. The kickstand itself looks to be the same model as the one off rockymountain. It looks big enough to hold up a building.

 

[Repp]

O I paid 3k got original owners man, bunch of oil filters, back carry rack, extra body bolts, extra plastics

 

[LandLubber]

7 hours ago, repp said:

O I paid 3k got original owners man, bunch of oil filters, back carry rack, extra body bolts, extra plastics

 

Good buy! My 06 525 is an old trusted friend. 

Also if your parking this thing at school your going to need some sort of theft deterrent. Thats a sweet bike and wont last long parked out in the open.

Edited April 21, 2018 by Bobatsea

[Repp]

Yup. Working on some theft deterrent now. I have progressive in case of total loss. Problem is, I will only receive $2000 or so after a $500 deductible if stolen. I bought a key ignition unit from Aliexpress for about $1.50. We will see how it holds up to weather. I saw a key ignition metal tab to fit the 2 bolt holes for the handlebars but I can't seem to find it again. I used CAD to draw up something similar that I plan to cut with the water jet. I want to wait until the part comes in to get the final geometry but it looks something like the pic below. I pretty much just copied what I remembered seeing. I want to tie it into the stock on/off circuit from the stock button. I'm also going to install another toggle somewhere on the bike for additional security. 

As far as a theft from just picking the bike up and taking it, I have been looking at some huge chain and padlocks that would be pretty hard to deal with. 

[S.O.A.N.Z]

4 hours ago, repp said:

As far as a theft from just picking the bike up and taking it, I have been looking at some huge chain and padlocks that would be pretty hard to deal with.

Angle grinder will still get thru it - if the thieves want it - they will get it

[theSteels]

12 hours ago, S.O.A.N.Z said:

Angle grinder will still get thru it - if the thieves want it - they will get it

I too am looking to install a locked ignition on my exc, do you recommend a better or simpler alternative?

 

Edited April 23, 2018 by theSteels

[Repp]

This sticker looks intimidating. I have also seen some brake rotor clamp things that make a bunch of noise when moved. Problem is, I can see myself pulling off with it attached and destroy my forks.  

[S.O.A.N.Z]

3 minutes ago, repp said:

This sticker looks intimidating. I have also seen some brake rotor clamp things that make a bunch of noise when moved. Problem is, I can see myself pulling off with it attached and destroy my forks.  

Or this sticker  

[SnowMule]

RFS is a great motor.  Take care of it (valve adj's, top-ends, oil changes, etc) and it'll last a while.

I have a keyswitch that grounds ignition when off, turns on electricals and headlight when in the "on" positions.  A disc lock will help keep it where it is... but get it insured.  Dualsports are cheap to insure.  Look into additional coverages for aftermarket accessories/etc if you're really concerned about it. 

As far as the disc lock reminder thing... I fold a mirror over when I locked the disc lock on.  Some locks come with a cord you can loop over the bars.  You'll notice it before you get too far, and before it does any damage.

You'll want a better headlight... trust me. 

Float the stator ground and do the "dc mod" (pretty easy, i bet a ME could do it, if not, find an EE friend ? ).  Gives you a lot more DC power, and running the headlight off DC means it doesn't dim at idle. 

Solidworks! ? Upgrading to 2018 here...

 

 

[SnowMule]

I would also advise replacing crank bearings with heavy-duty ball bearings vs. the roller bearings in there now.  Less chance of crank issues when using it as a dualsport/highway bike.  KTM 0625060206, you'll need one for each side. 

You'll also need to hone out the ID of the bearing to slip-fit over the crank before you press it into the case.

 

 

 

[Repp]

I like your dash setup. I will check into the DC mod. What light do you suggest? Also, I'm not able to check the compression right now until I go home but I'm itching just to take it apart and see the piston skirts and walls myself. I feel like I just have to see it. The last owner rode it 9 hours in 4 years and his buddy, the original owner, crashed it when it was new. I was told it scared him so it sat in the garage until he sold it to the guy I bought it from. The electronic hour meter was put on by the 9 hr guy so I really don't know where I am with engine wear/maintenance. The head bolts don't have any socket marks on them so I'm lead to believe it has never been into. I can tell when the 2 strokes need top ends but I'm in a new world now.

Also, what oil are you using? If you tell me sugar water, I will do the same looking at your odometer.  Love to see a bunch of miles

Edited April 24, 2018 by repp

[SnowMule]

Rotella T6.  Stainless filters - I haven't changed an oil filter since I bought the bike (~1000 mi on it).  Hose 'em out with carb spray, dry it with shop air, and shove it back in.

I do oil changes every 25-30hrs.  Blackstone Labs does engine oil analysis, their results are why I stretch out oil changes that far. 

 

Easy stator mod is to just pull the ground and shove all the power through a reg/rect.  A better way is to pick up a spool of magnet wire and rewind the stator, filling the poles, then put all that through the reg/rect.  TrailTech has a 150W reg/rect that works well, relatively inexpensive.   You'll need to mount it in the airbox, since it's larger than the stock 25W reg/rect and won't fit under the tank.

 

 

Did my first top-end at 6k miles, I do them every 6-7k or so (or if there's some reason I need to get into the engine). 

 

1mm oversize SS valves will extend your valve adjustment intervals significantly.  (Will need head work to make those fit.)

 

Headlight's off an '05 EXC (iirc).  55W H4 bulb.  Most of the electrical system on this bike is my design.

 

Seems to do okay. ?

[cobra46]

10 hours ago, SnowMule said:

RFS is a great motor.  Take care of it (valve adj's, top-ends, oil changes, etc) and it'll last a while.

I have a keyswitch that grounds ignition when off, turns on electricals and headlight when in the "on" positions.  A disc lock will help keep it where it is... but get it insured.  Dualsports are cheap to insure.  Look into additional coverages for aftermarket accessories/etc if you're really concerned about it. 

As far as the disc lock reminder thing... I fold a mirror over when I locked the disc lock on.  Some locks come with a cord you can loop over the bars.  You'll notice it before you get too far, and before it does any damage.

You'll want a better headlight... trust me. 

Float the stator ground and do the "dc mod" (pretty easy, i bet a ME could do it, if not, find an EE friend ).  Gives you a lot more DC power, and running the headlight off DC means it doesn't dim at idle. 

Solidworks! ? Upgrading to 2018 here...

 

 

Oh another SW guy.  I'm an ME too and drive SW 2017.  We always wait a bit before we upgrade.  Not sure if it's laziness or hoping most of the big bugs are updated.

[cobra46]

9 hours ago, repp said:

I like your dash setup. I will check into the DC mod. What light do you suggest? Also, I'm not able to check the compression right now until I go home but I'm itching just to take it apart and see the piston skirts and walls myself. I feel like I just have to see it. The last owner rode it 9 hours in 4 years and his buddy, the original owner, crashed it when it was new. I was told it scared him so it sat in the garage until he sold it to the guy I bought it from. The electronic hour meter was put on by the 9 hr guy so I really don't know where I am with engine wear/maintenance. The head bolts don't have any wrench marks on them so I'm lead to believe it has never been into. I can tell when the 2 strokes need top ends but I'm in a new world now.

Also, what oil are you using? If you tell me sugar water, I will do the same looking at your odometer.  Love to see a bunch of miles

I bought my bike with an unknown exact number of hours but when I got in the vicinity of 300-350 or so I noticed my oil consumption increasing to the point where, I carried oil in my pack on day two of a dual sport ride.

These bikes have soft intake valves and I was adjusting them a few times a year before I broke down and did a top end.  My bike got harder to start as the valve tightened.  Based on the recommendation of engine builders, I went with +1mm Kibblewhite intakes.  I have now substantially increased my valve check interval as they never move now.

At about 450 hours I suffered a main bearing failure in BFE Nevada due to crank spread.  I had the crank welded and replaced all the bottom end bearings.  I used Rotella T until they stopped selling it and now use T4.  My transmission and bottom end looked brand new.

I don't want to start an oil debate as you can read these until you graduate.  I'm of the camp that it's far more important to change your oil often than what kind of oil you use providing certain specifications are met.

[Repp]

I'm with you Cobra, I think changing the oil more frequently with Rotela is the path I'm taking. For pretty much everything, I tend to always start cheap and If I want better or more then I spend more. Most of the time for me, cheap works just fine. 

As far as top ends go. I see there is a 11:1 and a 12:1 option available from wiseco for about the same price. Do yal just put the 11:1 back in or bump it up? It's hot as camel nuts in Georgia so extra heat might not be so good without an aux fan. 

Edited April 24, 2018 by repp