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Sub Frame Lowering

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Hi,

I have a spare sub frame and am pretty short for the bike - wouldnt mind reaching the ground a bit better - any suggestions on how to mod the subframe?

I figure cutting a piece off the lower part and drilling the hole higher will lower the seat - but more at the back than anywhere, anything I can do to compensate. I can arrange ali welding so I'm not too fussed abt having to cut and weld if necessary.

Anyone done this yet? Got a link, any problems that were encountered?

Thanks in advance.

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Thanks,

theres some good reading there. I had some other ideas, pretty much the same to lower the rear (didnt think about "driving" the plugs deeper - thought id just put some new squre ali bar in there and wel it up); added to that I though about lowering at the front a little (just enough so that the subframe doesnt contact the shock/reservoir or whatever that bit is called). I fugure I needthe front lowered too, any thoughts on that?

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I lowered a sub-frame on my '01' 250sx. I hated it! The rear tire rubbed on the fender and the sub-frame broke on me at the weld. The shock rubbed on the air boot and wore a hole in it plus wore some alu. off the shock body.

Cutting the sub-frame only lowers the REAR of the seat and it is hardly noticeable. I cut 5mm out of the sub-frame just above the lower bolts and had it rewelded. It cost me $50 to get it done and about $400 to replace all the stuff that it ruined! Just buy the factory LOW seat. It is the way to go. It is only about $100 and it bolts right on with no problems.

P.S. I am 5'5"

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Factory Low seat? from the KTM dealership?

Only reason I am interested is that I have a spare sub frame, but if its going to ruin other parts its not worth it!

What kind of riding did you do with your SX Larry?

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Just my unhumble opinion, but...................

The lowering didn't ruin your subframe, the poor quality work and execution did. There's over 330 hours om my lowered subframe and not a single problem.

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330 hours???? any more info, not that your link to your KTM talk thread wasnt usefull. But:

1. How do you make 100% sure about the clearances before cutting?

2. Is it possible to drop the front of the seat (looking at it makes me think it will only drop slightly when lowering the subframe from the back/bottom bolts). - I considered maybe welding some ali square bar strips (3" pieces maybe) to the top of the SF where it bolts to the fram at the front by the tank, and then drilling the holes in the new square bar - just high enough to clear the shock reservoir - is that an option perhaps, obviouslytogether with lowering the back?

3. Can it be lowered too far? Ie: I want to be able to reach the ground with flat feet and highside less, but if i go too far will it be uncomfortable when seated, anyone find that is a problem at all?

Thanks for the replies, even though there are different opinions - good to hear them all.

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Factory Low seat? from the KTM dealership?

Only reason I am interested is that I have a spare sub frame, but if its going to ruin other parts its not worth it!

What kind of riding did you do with your SX Larry?

I race MX. I never go trail riding!

The part # for the factory LOW seat for the 08'-09' bike is 77307040200. It is listed at $100.77 in the KTM hard equipment.

My sub-frame broke on a FACTORY weld not on the weld that lowered the sub-frame. When you lower a sub-frame it puts your pipe in a bind and when the shock bottoms out it rubs the shock body on the air boot. You can play around with the pipe mounts to correct for it but there is not much you can do about the shock rubbing on the air boot.

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I see, thanks Larry.

I dunno if i would lower my bike for MX - its not that bad for me. But I really wouldnt mind it lower for trails. It obviously rubs on the airbox on the "downwind side" of the airfilter - ie: on the "boot" between the filter and the carb? I have the other part spare (where the filter goes in).

Will try find a lower seat then, mines a '03 though - but will have a look.

Cheers

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Again, I stick to my statements above, Larry may be having problems with his pipe and shock, but I don't. One aberation does not disprove a concept.....................

I've done two of my bikes (525EXC and a 200SX) with absolutely no problems. NO shock rubbing, NO pipe rubbing (you do have to trim a little off the pipe juncture to make it work right), and no air box problems. Take a look at the pictures in the post. I've done three other friends bikes (another 525EXC, a 300MXC, and a 450Sx) and all worked out fine, and have been for a couple years now (go take a look at the date of the post in the link). Several guys on KTMTalk have done the lowering, and no problems that I've heard of.

Larry, I'm sorry to hear how you had problems with yours, but just because you have had one failure (on a completely different method, note this is the no weld style), does not make every lowering job a failure. There are several examples of sucessful lowering jobs done, not just here but in may forums.

I'll let this dead horse lie now.............beatdeadhorse.gif

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I see, thanks Larry.

I dunno if i would lower my bike for MX - its not that bad for me. But I really wouldnt mind it lower for trails. It obviously rubs on the airbox on the "downwind side" of the airfilter - ie: on the "boot" between the filter and the carb? I have the other part spare (where the filter goes in).

Will try find a lower seat then, mines a '03 though - but will have a look.

Cheers

The # for the low seat that fits your '03' is 54807040600 and it is $91.95. That is the same seat that I have on my '06' 250sx.

As I said in my first post , the bike I did was an '01' 250sx. It was a completely different bike than your '03'. It had a different frame, motor, sub-frame, forks, carb, air box, swingarm and just about every other part on the bike. It did have the same rear wheel but the hub was a different color!

Get the low seat, you will love it!

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