Bill_RC1

Member
Mar 29, 2001
15
0
Just purchased a 01 520 SX - will have next week. This is my first KTM and first 4-stroke. (over 20 yrs of 2-stroke riding)

I'm having the forks/shock revalved and springs for my weight/riding - MX and desert. I'm installing 18 mm offset triple clamps, T-4 Pro-Circuit Muffler, skid plate, SS clutch cable with EE lever and the other standard look good stuff.

I've read/seen posted about rerouting the crankcase hose, P-38 carb mod, plugs and such. But just looking for some additional thoughts from guys that have the 520/400 SX and mods that have worked good on your bike and any suggestions from KTM/4-stroke riders.
 

MARK # 51

Member
Apr 18, 2000
30
0
i have the 01 520sx with many of the same mods. as far as the ee lever and steel line goes, i would pass on that it really didnt make any difference at all. the stock system on the 520 is a very easy pull. i took my works connection skid plate back off because of the increase of engine noise. it made it sound like the engine was comming apart! the 18 mm clamps are a good move. the best mod i did was a 20" excel with a 739 and buchannan spokes. i never felt really confident in the front end until now. this makes a hugh difference that you will feel, even at the novice level.

------------------
 

Scott in KC

~SPONSOR~
Aug 28, 2000
212
0
Mark, you just hit on something with that skidplate noise thing. My Husaberg seems a little noisier than normal, nothing extreme just a little rattle (please, no Husaberg jokes)
smile.gif
The previous owner said it's always done it, I have no reason to doubt that. But that would make sense, you have a metal megaphone thowing that gearbox noise right up at you. Maybe some foam would help.
 

KDC

Member
Oct 16, 2000
7
0
I've had my 520 MXC for a couple of weeks and have done a few mods to it, like a BigGun exhaust, skid plate and etc. I'm curious about the 18 mm offset triple clamps? How will they help the performance of my bike? Wont that cause some headshake? And which make would you recommend?
 

Bill_RC1

Member
Mar 29, 2001
15
0
Originally posted by KDC:
I've had my 520 MXC for a couple of weeks and have done a few mods to it, like a BigGun exhaust, skid plate and etc. I'm curious about the 18 mm offset triple clamps? How will they help the performance of my bike? Wont that cause some headshake? And which make would you recommend?

I was informed by several riders and mag articles that the 18 and 16.0 mm ofset triple clamps greatly improve the turning of the KTM - can't run the 16.0 mm offset on the 2-stroke due to pipe clearance. I'm putting on a set from Applied Racing - won't have my bike out until next weekend put I'll let you know what I think about them.

I won't with the 18.0 mm for the head shake issue. Will feed back and let you know if I get any.

Did you have to do any re-jetting with the exhaust system? I know on 2-strokes you always do but what about the 4-stroke.
 

KTM400EXC#232

Member
Mar 19, 2001
22
0
Originally posted by Scott in KC:
Mark, you just hit on something with that skidplate noise thing. My Husaberg seems a little noisier than normal, nothing extreme just a little rattle (please, no Husaberg jokes)
smile.gif
The previous owner said it's always done it, I have no reason to doubt that. But that would make sense, you have a metal megaphone thowing that gearbox noise right up at you. Maybe some foam would help.

Use a section 40mm open cell foam between case and bash plate, wide enough to fit between frame rails and long enough from rear cross beam up to front of case. The open cell allows water and dirt to drain away. This stuff stops the (engine about to grenade) megaphone effect.

------------------
go on, brake late, my mum does!
 

KDC

Member
Oct 16, 2000
7
0
I had the "quiet core" in the Big Gun at first, which, didn't require any jetting change; only a fuel adjustment scew adjustment. Then I put the "racing core" in, which required going (one) up on the pilot and (two) up on the main
Originally posted by Bill_RC1:
I was informed by several riders and mag articles that the 18 and 16.0 mm ofset triple clamps greatly improve the turning of the KTM - can't run the 16.0 mm offset on the 2-stroke due to pipe clearance. I'm putting on a set from Applied Racing - won't have my bike out until next weekend put I'll let you know what I think about them.

I won't with the 18.0 mm for the head shake issue. Will feed back and let you know if I get any.

Did you have to do any re-jetting with the exhaust system? I know on 2-strokes you always do but what about the 4-stroke.
 

Bill_RC1

Member
Mar 29, 2001
15
0
520 SX Update -- rode the bike today for the first time. Will never go back to a 2-stroke and was able to clear those big doubles and table tops with no problems on the 520. Used to scream the CR250 to do what the 520 does amost at idle. Amazing bike.

18.0 offset clamps -- no head shake and the bike turns on a dime.

T-4 ProCircuit exhaust -- nice muffler. Motor just runs clear thru the RPM. Can ride the whole MX track 2nd.

Disconnected the crankcase vent tube from the carb and routed between the radiators. Only problem was that you can smell the oil.

Question for other 520/400 owners -- when the bike is on the bike stand and in neutral when I roll the rear tire their is a lot of noise being generated. I know some is the chain but I'm concerned that some is coming from the front sprocket/trany -- just seams like a lot of noise from this area.

2nd - when checking for jetting with the T-4 Muffler do you check the plug like a 2-stroke for color and determine if it needs changing?

Any help will be nice.



------------------
 

KTM400MAN

Member
Sep 6, 2000
76
0
Bill, put a breather filter on the end of the breather line, it should cut down on the smell since it helps keep the oil from dripping down onto the engine. Or you can run the breather line into the airbox or up under the tank, back behind the carb., and down to where the carb. vent tubes exit by the swingarm. The noise you are describing
sounds like what I hear once in a while on my bike when I dont have the bike cleanly in neutral. If you haven't gotten your new triple clamps yet, go with the 16mm offset clamps and move your back wheel rearward as much as possible in the slot. You'll probably have to wait till you need a new chain and sprocket though. (expensive fix!) Factory R&D makes their T/C's out of Scandium, which is stronger and lighter than aluminum. Erik

------------------
visit our club's website at www.ruts.org
 

Bill_RC1

Member
Mar 29, 2001
15
0
The noise you are describing sounds like what I hear once in a while on my bike when I dont have the bike cleanly in neutral.

KTM400MAN - when you have your bike on the stand and idling in neutral do you here a noise - like a bearing chattering - but when you pull in the clutch it stops - let the clutch out and the noise starts. Very loud noise that stops and starts when you pull the clutch in.

I may just be over-picky but while the 520 is still under warranty if anyone else has had this issue I want to correct it quickly.



------------------
 

katoomed00

Member
Nov 18, 2000
24
0
I noticed the same noise,but it was almost undetectable when i put more slack in the chain,quite abit louder if the chain is to tight.
also i have a carbon fiber skid plate and the engine is not as loud as you describe and when the clutch is disengaged there is no noise,i did remove the plate and it did make a difference in db

------------------
 

Smail's98KTM

Member
Apr 10, 2001
25
0
Throw a header and silencer on that mean mutha...you will feel the performance..on 4 strokes the stock exhaust is very restrictive by opening it up the bike will breathe better thus increasing power.. hope i could help...

------------------
Katooms rule
 

Bill_RC1

Member
Mar 29, 2001
15
0
Thanks for the replys -- I will loosen the chain up some and check the nosie out. I have a tendency to over-tighten chains and I may have done that when I put on the 50 tooth rear sprocket. I have the aluminum skid plate on the bike and as everyone has stated it makes the engine noises louder.

I have the T-4 Pro-Circuit Muffler on the bike with the 2" endcap. Looks like you can craw down the pipe and inspect the exhaust valves its so big!

Power is unreal with this bike -- my biggest problem out the first time was to stop over-jumping the doubles. They use to be a challange on the CR250, came up short several times, now I clear with ease. This bike loves to jump.

------------------
 

Shaw520

Damn Yankees
LIFETIME SPONSOR
May 14, 2000
1,082
6
Originally posted by Bill_RC1:
Very loud noise that stops and starts when you pull the clutch in.

The clutch chatter is common w/alot RFS's, has'nt proved to be a problem though.
smile.gif




------------------
Faster Bikes, Younger Women, & Older Whiskey
AMA
BRC
 


Top Bottom