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I just bought an '03 EXC450. The bike is street legal, had low hours, and a good history. I bought it for the plate. The bike will probably be used 60% street, ( gravel roads, county blacktop, little if any in town stoplight stuff), 40% trail riding. I make a concious effort to shift smoothy on asphalt due to the lack of a cush hub and don't rev the snot out of it because I really don't need to. I've richened up the stock jetting and it hasn't steamed the two times I've ridden it on slow 1st gear single track. It has no fan, I'll probably put a catch tank on it. It has 14/50 gearing and I probably won't run it over 50 mph on the street. I've put about 120 miles on it in the last week and it's alot of fun to ride.

Anyway, I know there is some RFS owners here and would like to know how many miles they have put on their bikes and have they been pretty reliable. I've been riding Lc4's for the last 10 years and I haven't been able to kill any of them, and I have tried. I know the maintenance schedule is tighter on an RFS compared to an Lc4, that's not a big deal. I'll ride it for awhile and see if it's a keeper. It takes me awhile to warm up to a new bike and trust it the way I do my old "established stuff". Interested in peoples thoughts that have owned this bike, or RFS's in general.

Thanks

-Harvey
'98 RXCe620
'02 EXC300
'98 FXRS
'03 EXC450

XR- there's a few bikes I always wanted to own and a 450 with a plate is one of them. This bike only had 39 hours on it, looks new and I was able to get in it right so I bought it. It's stupid fun to ride, especially on the back roads. I also think a 950 Adventure is on my short list of bikes to own in the near future. Time to start livin' some. I spend too much time behind a desk serving my "Corporate Masters". I'll have to take a zero on the Iron Butt. Don;t currently have anything that can keep pace with the Beemer.....

-Harvey

I've owned both LC4s and RFSs. For my kind of riding (shorter distances, more trail and serious off-road) the RFS excels. Lighter, more flickable, far more responsive (even than my 625 SXC), far lighter and much easier in the woods. I should never have sold my '03 450 to Jeff (that lucky dog) but I did. He is enjoying it now. I think the '03 was a classic year for the combination of performance and handling.

I read on ADVRider and in KTMTalk that some guys have up to 30,000 miles on their RFS engines. The guys at Letko tell me that they just don't see them in there for service. "If I were depending on the RFS service work to keep bread on the table I would starve." said one of the guys there.

I replaced my 450 EXC with a 525 EXC. The difference is that the 525 is simply, wonderfully, violent and extremely user unfriendly. You had better be ready to be slammed down hard when riding this thing. Yanking the throttle wide when at a low RPM will get the bike attempting to toss you off the back side. The 450 is a better bike all around unless you are hitting the long distance Baja trails (not a lot of those around here) or you just like outrunning every Corvette you come across.

Maintenance? Keep the oil clean. If that means change it every 4 hours then do so. Check the valves once in a while. That will cost you two valve cover gaskets and some time. The maintenance schedule on my 525 EXC is exactly the same as on the 625 SXC. Failures? I hit a tree once and tore my clutch cable off. It was all KTM's fault.

Stu

Thanks Stu!

TF already knows my opinion.

The RFS are establishing themselves as one of the most reliable moto motors to ever see the trail...you know real motors...not the go-kart 14 hp ones on red bikes!

I see lots of threads with guys running 20K+ miles...and one of the Dirt Rider owned bikes has 50k miles and has never been apart.

They are a dream to work on...easy oil change...valve adjust in 40 minutes (no shims!)...just splendid.

I have liked every RFS I have thrown a leg over. My old 400 lives on with a Kansan now....it is going strong.

I got an '04 450exc, not plated and only set up for Colorado goat trails with 43 hours on it. Ok, in no certain order here's my take on it.

On the '04 bikes, ktm changed the rear shock spring to a straight wound from the '03's progressive wound. From riding an '03, the rear suspension could take a bigger hit than mine. Mine's too plush for anything other than root and rock infested single tracks. Fiddling with the compression and rebound adjustments didn't help the bottoming one bit. The forks bottom out just about as bad as the rear shock. I've not had the suspension revalved or kitted since, it works for the majority of the use it gets.

As far as power, the '03 had the dual header pipe and in '04 they went to a single pipe. I thought the '03's had better low end torque but, the '04's had a tad more mid range. When I went to an fmf factory 4.1 with spark arrester, from puttin' a big dent in the stock header, the engine woke up with a gps indicated 93mph wfo blast down a dirt road. Stock it would only do 88mph in 6th gear. To give some perspective on top speed, a riding buddy's '03 525exc with stock gearing would do about 94mph (we were at 10,100ft elevation). Oh, also I've got 14/52 gears in mine. It'd still climb them 14,000 ft trails ok even though I lost some low end. Basically, what I'm gettin' at is that the stock muffler is restrictive and the power gained from a more open system is worth a few ponies. Also, the stock exhaust will ruin many pants unless some heat guards are added; one on the front and one near the rear side panel.

On the engine maintence side, I'd adusted the valves twice; once at three hours and the other at 28. Both times, the exhausts were loose and the intakes tight. It's clicking/rattling a bit now, so, I should probably take a look at it again. I do have a ktm fan kit on mine since it tends to run hot at something like walking speed. Anything faster and it's ok. Mine also boils gas up and out the gas cap overflow tube when the ambient temp's over something like 90 degrees or if it's idled too long. An insulation heat tape blanket thing seems to help; the exhaust pipe is really close to the tank. I do have one of them carbon fiber carburetor insulation pieces as well; the pipe's real close to the carb, too. If you need some factory manuals, I have some in .pdf format ... as a matter of fact the '04's used the '03 manual.

In regards to handling, I don't race the thing and it works just fine for the occasional trail riding I do. My back ground's in mx two strokes so, the bike tends to wash out and feel heavy on the front end, especially in deep sand. But, up in them mountains, I do not have one complaint. It's easy to get the jetting right, too. After a 35 mile ride on Star trail, I'm still ready for some more; probably that electric start thing. It's a dang good bike.

Check your rear sag. It is critical for the rear end keeping the knobs on the ground AND for helping with the pushing on the front end. If it is off it will push badly. I have had tires slide across an intersection on the street from this. Not cool.

Stu

I took the afternoon off yesterday and went to Perry and rode solo for a couple hours on the 450. I looked at it as therapy. I needed it. It's geared 14-50 which for me seems to be an almost perfect balance for street/single track. Both the front and rear suspension felt pretty harsh especially on cross grain chop. I settled on the F&R comp damping 6 clicks from full soft and the rear preload three turns on the ring from full soft. This is outside the recommended setting but smoothed it out considerably for woods riding. The bike sticks in the corners and turns well so I'm good with it for now, until the suspension gets some time on it. The bike feels like a bicycle compared to my 620.

Bike has plenty of nice smooth power but will put you on your ass if you get ham-fisted with the throttle. I'm going to O-ring the accel pump and see if that helps the VERY slight bog right when you whack the throttle open to lift the front wheel. If you are cognizant and are always in the right gear, have the RPM correct, and are set up properly for the obstacle, the bog does not occur, only when you are "riding lazy" will it happen. I may JD/diaphram it, I don't know yet. It really runs pretty good as is.

The bike will chug pretty good but not as good as my 300. Sometimes you get caught in the wrong gear, (to high) and need to downshift but can't. The 450 will start growling pretty loud wanting a lower gear where the 300 just vibrates a bit more and pulls itself out of it with little drama. Both bikes are geared comparably. You could put a FWW on it which may help. I personally woudn't want to gear it down anymore, however, some guys like the 14-52 setup. If you are wanting to ride the 450 fast, it seems to demand more rider commitment compared to the 300. I also noticed the compression braking as well.

The bike is perfectly suited for single track that flows reasonably well. The bike would be alot of fun in Arkansas, of course you guys that own RFS's know that. I've never ridden a Husky but I suspect the TE models would be very comparable to the KTM's. I hauled it to Perry to save the knobs but to take a break I went out on the street to cool off, just because I could. I had it up to 65 and it seemed to still have quite abit left. It would wheelie easily in 3rd gear. You just feel like you're breaking the law when you ride this thing on the street.

Just some observations. As always, YMMV.

-Harvey

I do remember the bog issue with my bike as well. From what I can remember, I went down to the local Honda dealership and bought the complete accelerator pump assembly for a CRF450R. I believe, it cost a whopping $19.00. Kinda cheap for a Honda part (although it is genuine Keihin). Back in '04, that seemed to be the popular thing to do for the rfs motors. A couple of ridding buddies with '03 525s did the drilling and tapping thing to limit the pump arm travel like they used to do for WR426s. Also, a big knobbed fuel screw with o-rings on the top and bottom makes for easier adjustments. Got a china made one from rocky mt atv for around $10.00.

A couple of things:

1) Get the KTM mixture adjuster screw. It is more money but it is plated brass and will not seize in the bore the way some of the aluminum ones do.

2) The Honda diaphram for the Keihin carb is all you need. It restricts the fuel available to squirt in from the accelerator pump which cuts out the bogging.

3) I pretty much stayed with the stock lean jetting (I think I went up one on the pilot jet) and installed the HT-Racing intake vane to take up some of the volume in the intake. It worked wonders on my 525. Ask Bill Thomas at HT about the use of it on the 450. That ended the bog (unless I am really dumb with the throttle, and that happens...).

Stu