Gearing down '07 525EXC...

Has anyone done any gearing down on final drive for '07 KTM EXC 525? Awesome bike, but geared too high for single tracks. I usually do versatile riding: the terrain in AZ changes severely, so as type of riding: from flying open desert to navigating highly technical steep rocky single tracks. I wouldn't mind to sacrifice some top speed in order to gain that low end torque on first three gears. Other than that... the best set of two wheels- great weight/power ratio. I had to strip all that "european" stuff: huge controls/housings, blinkers, 3' long tail, extra covers, key ignition and fork lock (duh! try to deal with it if you loose your keys out there in the desert!).

Any experience with this bike or similar?

I run 14/53 on my 01 426....works great on the upper sycamore singletrack...but youve got the bike I want.....I want something street legal so I can play "connect the trails"...

im 6'1 220......you dont think its too heavy for the singletrack..???

I know a guy who had one , and he stepped down to a 450 for better manueverability in the tight stuff..they are soo close,I cant imagine they would be much different..

Ratio I definitely need to achieve on mine.

NOt at all- I mean not heavy for single tracks: there isn't such thing! I know few guys, your size and bigger, with big bikes like 426, XR650, or 525s: they fly single tracks!

I also run street legal, I live in Carefree (north end of Pima/Dynamite power line, beginning of Seven Springs and Bartlett areas), ride right from my back yard. Though I had to remove all that extra junk we are not required to have in AZ, such as blinkers and HUGE, ugly mirrors- perlaced with light, small Acerbis left mirror.

I still have an old, good XR400 for VERY tight stuff. I am 5'-9", 130 lbs, I've tried most of bigger KTMs: 450, 525, 640/625, even 950 (last two are too heavy for a girl to pickup if I were to crash, and definitely are not meant for AZ tight stuff). Seat height doesn't matter for me, like it does for most of girls. Seems like the weight and manueverability difference between 525 and 450 is insignificant, but the power gain is excellent. In fact, I am looking at the website right now: both EXCs- 450 and 525- have the same dry weight: 250 lbs. The same suspension, the same frame. And it's only 13 lbs heavier than my light, air-cooled XR400.

I love my 525 by all means, except for the gearing: definitely will swap the sprockets to get 14/53 or even lower. I was just wondering if this would be sufficient, and no "internal" work needed.

I was going to put a flywheel weight on my 426.....but after changing the sprockets I found that that was enough...Its like a tractor...lots of low end climbing power....I did sacrifice some of the top end...but 80 percent of my riding is thru 2nd to fourth gear..then back down...I rarely have tapped this bike out..

Im in Apache junction...My sister has a cabin at forest lakes upon the rim...Im envisioning a ride up there...connecting trails by short sections of hiway...I think the 525 is what I need.

i run a 14-50 on my 07 525 exc...flip the axle blocks and u don't need a chain

I went to 13/48 on my '07 450EXC. Seems about perfect for everything now. That, and getting the jetting and exhaust opened up has made the bike super!

The stock 15/45 was for the freeways.

I run 14/52 now works nice and will still run 90 or a little better... I started with 14/48 that works good all around but I find myself in some nasty spots at times so I went with the 52 in the rear...

14/48 - great for open and if your a compitent rider also good for single track and hills, you just need to be on your game and carry more speed

for very tecnical hills first gear is not a problem with this ratio

if you like wheelies youl be overtaking people that are tapped out doin 100 kmh , i love that

With the 14/52 do you need to make any changes to the chain? I have a new 07 450exc and was thinking about 14/48 at first, but being in Colorado I know how wicked:eek: it can get in the bad spots.

14/48 - great for open and if your a compitent rider also good for single track and hills, you just need to be on your game and carry more speed

for very tecnical hills first gear is not a problem with this ratio

if you like wheelies youl be overtaking people that are tapped out doin 100 kmh , i love that

We have quite rugged riding terrain here in some parts of AZ, not just up and down, but miles and miles of vertical and horizontal very tight stuff, and very rocky- no such thing as conventional mud, unless we head out to the open spaces in southern parts of the State or Mexico, or run sandy washes. Gets too old doing majority of your riding on 1st gear for hours when most of it is a a very technical single track. Hard on the bike too. Again, what's the need for 6th gear on dirt bike? If I want to ride flat and fast, I'll take my sport bike to the track. I guess when KTM decided to call it "street legal" they assumed it's for some street/forest service easy roads riding and changed gearing. However, for us "street legal" means just to hop from one riding area to another or like myself living close enough just to ride from the back yard without getting cops on your a$$ for running unlicensed vehicles on public roads.

With the 14/52 do you need to make any changes to the chain? I have a new 07 450exc and was thinking about 14/48 at first, but being in Colorado I know how wicked:eek: it can get in the bad spots.

I've heard 14/53 too plus different chain too.

It sure does get wicked: besides AZ, I ride in Utah and sometimes in SW Colorado. Most of my riding here is on single tracks or very tight trails wide enough for quads. But also, in between there are big sand washes where you want to run wide open, the faster the better. So, the terrain is far from being uniform for any patricular type of riding. Unlike my old Hondas, KTM still gives plenty of top speed on higher gears, even if you gear it down.

I normally run a 14/51 on my 04 525EXC, which has the same trans as the 07's. It has plenty of bark on the bottom and can still handle the high spead washes in the Southern California deserts. When I head to Glamis or Kennedy Meadows I run a 13/51. This gives me that unltra low 1st for bouncing over rocks and keeps my in sweet spot of the RPM's in teh sand dunes. As far as being scared of buying the wrong setup, just experiment. I seem to only get a year out of my chain and sprocket setup.

I normally run a 14/51 on my 04 525EXC, which has the same trans as the 07's. It has plenty of bark on the bottom and can still handle the high spead washes in the Southern California deserts. When I head to Glamis or Kennedy Meadows I run a 13/51. This gives me that unltra low 1st for bouncing over rocks and keeps my in sweet spot of the RPM's in teh sand dunes. As far as being scared of buying the wrong setup, just experiment. I seem to only get a year out of my chain and sprocket setup.

I relate to So Cal desert (originally from SD area), we have some similar stuff here in my neighborhood: Carefree/Cave Creek/Bartlett areas- very rocky, very tight, entirely solid granite trails covered with sand/crushed rock and more than you need cactus to dodge around. Reeally need that low range and desert tires! Sometimes any bike seems too long to get around boulders or cholla (JK), or too wide- catches radiator shroud or pegs on the banks of deep Vs.

I rhink I'll try 13/51 or 13/52. I don't really go to Glamis or Imperial, only occasionally with group of friends, but we have plenty or big sandy washes and river beds around here. Again- as you say: always good to experiment and make changes.

07 525 EXC stock is 15-42, changed to a 13 - 48 too much for first and second. I'm at a 14 - 48 now and it feels real good. Don't need more because the bike has the torque to NOT need more gear, it's not a 450 it doesn't need those low gears it has an excessive torque band, gear too low and you'll lose any usefullness of first and second gear. DVASQUEZ above say's it pretty well.

07 525 EXC stock is 15-42, changed to a 13 - 48 too much for first and second. I'm at a 14 - 48 now and it feels real good. Don't need more because the bike has the torque to NOT need more gear, it's not a 450 it doesn't need those low gears it has an excessive torque band, gear too low and you'll lose any usefullness of first and second gear. DVASQUEZ above say's it pretty well.

Exactly:applause:

Replaced stock on my '07 525 for 14/52 last night, will try out on single tracks and on some fast sections this afternoon...see if it works well or needs something different.

07 525 EXC stock is 15-42, changed to a 13 - 48 too much for first and second. I'm at a 14 - 48 now and it feels real good. Don't need more because the bike has the torque to NOT need more gear, it's not a 450 it doesn't need those low gears it has an excessive torque band, gear too low and you'll lose any usefullness of first and second gear. DVASQUEZ above say's it pretty well.

Do they come in two different options? All sources give two ratios:

15:45 and 14:50? What's the second ratio applicable to- sounds like a better option. Suggested mod?

Nothing about 15:42 though....

(I really haven't counted number of teeth on the sprockets!)

Do they come in two different options? All sources give two ratios:

15:45 and 14:50? What's the second ratio applicable to- sounds like a better option. Suggested mod?

Nothing about 15:42 though....

(I really haven't counted number of teeth on the sprockets!)

mine came 15/45 im sure thats what yours is too... if your afraid of getting to low try the 14/48 first thats what i did and it works very well... I have now put a 52 on that works good in the very tight stuff still will pull alittle better than 90mph... Tom

I would guess that the 15x45 was more about meeting some countrys sound test then anything related to performance. The range of 14x48 thru 14X52 is very workable. Some gear lower but there is no gear that someone will not gear lower. Gearing too low just makes the bike more violent and prone to spin the tire, big motor needs to have a load against it to be managable, yes your going to have to use the clutch in the woods, get used to it

Just tested 14/52, both-single tracks and open dirt road. Feels great on tight stuff: good gear choices. And runs very well on open (forest service) dirt roads and wide straight sandy wash, so as on Bartlett Dam Rd (paved). I don't think I'll ever try to "enjoy" interstates or any major highways on this one or any dirt bikes.

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