RFS valvetrain discussion (continued)

[Thump]

Mike did not give me the info. H&H did. The part number you just gave is for the EXC/MXC and does not work for the SX!

Order the part 590.36.28.144 for the SX and let us know what part number you get. Eric did just that and got 594.36.028.044 and I was told the same on the phone.

 

[dstktmusa]

I have checked with H&H through the website and here is what I have found http://www.ktmpartsearch.com/PartSearch.asp The old 590.36.028.144 part number will supercede to the 590.36.028.244 number NOT the conical design. (594.36.028.044)

 

[dstktmusa]

Hit the link then ad the part number 590.36.028.144 and see where it takes you.

 

[dstktmusa]

Originally posted by Thump
Order the part 590.36.28.144 for the SX and let us know what part number you get. Eric did just that and got 594.36.028.044 and I was told the same on the phone.

You get this part number 590.36.028.244 which is the 2 spring design like in the 2003's

Nothing supercede's to the 594.36.028.044

 

[Rich Rohrich]

Originally posted by BCR-Bob
In the original thread EG made a statement about people not doing proper maintenance and the results he has seen due to this. By reading his post am I to believe that the spring failures he saw were in some way related to lack of proper maintenance in his opinion?

I asked Eric about this and a couple of the recent failures he has seen were on bikes that were well maintained by qualified people. So while poor maintenance practices are bound to make any problem of this nature worse, I'm not sure it can be completely written off to that.

 

[Thump]

Originally posted by dstktmusa
You get this part number 590.36.028.244 which is the 2 spring design like in the 2003's

Nothing supercede's to the 594.36.028.044

ORDER THE PART! and see what you get... then see if it fits! The freaking head was changed in 03' by making the recess 2mm larger. It does not work on the 01/02 models according to the information I have been given.

I don't know why you are on a quest to prove Eric and myself wrong... This whole thing started out because Eric had a problem while rebuilding a motor and he passed it along. There is an easy fix to this problem.

 

[Thump]

Tell ya what dst call me, lets discuss it. 214.987.6537

 

[dstktmusa]

I called a KTM dealer that stocked part number 590.36.028.244 and asked them to remove the parts from the box. It was the 2 spring set up. It does fit the EXC/MXC 450/520 and it will fit any 400/520 RFS.

The 2003 450/525 MXC/EXC cylinderhead was changed ONLY FOR THE 12MM SPARK PLUG HOLE otherwise the head is the same as 2000-2002 and the part number 590.36.028.244 WILL fit the head.

The 525/450SX cylinderhead's were changed for the spark plug hole (12mm) and the 594.36.028.044 conical spring design.

 

[MrLuckey]

So as per the discussion is this correct?:

part # 590.36.028.144 is the OLD 2 spring style for 400/520

part # 590.36.028.244 is the NEW 2 spring style for 400/520 and should work in the '02 and older SX's

part # 590.36.028.044 is the NEW conical spring style for ' 03 450/525 SX ONLY

And now there is a question as to what you will get if you order part # 590.36.028.144

So is there a possibility that KTM is merely shipping the incorrect part?

 

[dstktmusa]

Originally posted by TTRGuy
So as per the discussion is this correct?:

part # 590.36.028.144 is the OLD 2 spring style for 400/520

CORRECT

part # 590.36.028.244 is the NEW 2 spring style for 400/520 and should work in the '02 and older SX's

CORRECT AND WILL FIT IN THE 2003 EXC/MXC

part # 590.36.028.044 is the NEW conical spring style for ' 03 450/525 SX ONLY

NOT CORRECT, 594.36.028.044 IS THE CONICAL SPRING AND FOR THE 2003 SX' ONLY


And now there is a question as to what you will get if you order part # 590.36.028.144

THIS PART WILL SUPERCEDE TO 590.36.028.244

So is there a possibility that KTM is merely shipping the incorrect part?

ALWAYS POSSIBLE

 

[MrLuckey]

Quoted by me "part # 590.36.028.044 is the NEW conical spring style for ' 03 450/525 SX ONLY"

Quoted by dstkmusa "NOT CORRECT, 594.36.028.044 IS THE CONICAL SPRING AND FOR THE 2003 SX' ONLY"

Didn't you just say the same thing I did - that it is the NEW conical style for the '03 SX only ? Just trying not to get confused again.

 

[Patman]

Ok maybe to simplify this the solution is HERE for your RFS valve train parts. No he said / she said superseded incorrectly packaged mumbo jumbo.

 

[dstktmusa]

The first 3 numbers are the key. 590 vs 594

 

[MrLuckey]

Sorry bout that Dtk - I typoed that first part.

PatMan - Sounds good to me, heck we all have all kinds of aftermarket goodies hanging all over the exterior of our bikes. Might as well have some good stuff on the inside where it matters most.

 

[SFO]

Originally posted by BCR-Bob
As I stated in the original thread, I had repeated sring failures on a LC4 with both factory and aftermarket springs. I also said that the engine had an aftermarket cam in it.

Not to get sideways yet again but what aftermarket cam and aftermarket spring kit were you having problems with specifically?

 

[Thump]

Okay... I just got off the phone with Mike Rosso (sp?) Technical Director for KTM. I don't know for sure that he is legit, hopefully somebody here knows, but he sounded pretty knowledgeable. They have been watching this for a while and here is what we discussed.

The 01/02 SX uses the same head as the 03 MXC/EXC and according to him all parts fit. The only difference is that in 03' they have gone to a larger spark plug so the head is different. The springs are the same 2-spring design as they were in 01/02. If you order the old springs for the SX you get the new springs for the EXC/MXC.

I asked how he could have gotten the wrong springs? So he looked it up in the book. Page 12 shows 3 part numbers I a row.
1) the # for the 250
2) the # for the 03' SX (the 594#)
3) the # for the 03' MXC/EXC (the 590#)

Page 16 is SX only and the 594# is there again. I said so it is in 2 places and could have been confused by whoever was filling or placing the order? Yes.

Mike also told me that they had no warranty claims for the springs breaking... I asked if they were a warranted item? He said no. So I said than you wouldn't necessarily get a warranty claim for it would you? He said no. He said they have sold 54 springs said many went to Cooper's bike (about 40) so he did not feel it was an epidemic problem. I asked if people were replacing with aftermarket like the Kibblewhite they may not hear about the problem... He said it was possible.

Bottom line according to my phone conversation with Mike KTM is shipping the correct parts and does not think there is a failure issue with the springs.

If I owned a 400/520 I would replace the springs with the Kibblewhites to be safe because I trust what Eric says and choose to error on the side of caution.

 

[BCR-Bob]

I didn't really have a problem with the cam, just the springs. The cam was by Megacycle Cams. It had .450 lift and 264 duration and no auto compression release (yes it was a real bear to start at times). The stock springs didn't last too long with it. The only replacement springs I could find were made by R/D Spring. They would last about a season before the intakes would break at the lower coils. Like I said earlier, I just accepted the fact that I would be replacing them more than I would have liked, no big deal. The bike ran pretty good for what it was at the time, just way too heavy(even stripped down for desert racing). I'm sure there were/are other sources at the time (97-99), but I wasn't aware of them. I have a higher comp piston in my RFS (12:1) and would interested in any info and experience with cams for it. Thanks

 

[Patman]

This is reaching comical proportions but for the most part is a good discussion (not everyone may agree).

What I find interesting is that at one point we were told "the same springs were used on the LC4" and BCR-Bob has stated he experienced this very problem of lower coil failure when using a performance cam. Now if the LC4 and RFS use the same cam maybe this is a moot point but being a betting man I'll venture they are different designs (call it a hunch). Again not an epidemic but it seems to be something for consideration if indeed they really do use the same springs. I'm also willing to bet that dstktmusa is at the very least not the same individual I had discussions over the synthetic oil / clutch slippage debacle about 18 months ago if that user is now infact Mike Russo, OK actually I KNOW it's not.

What I do find confusing is that the discussion of a part number being right or wrong is not consistant throughout. Why are the dealers seeming to have a difficult time getting the correct piece? I mean who exactly is to be the authority when we go into our local shop to order a part? Should every parts order be disected before you leave with your bag of goodies? Why is it that the only people that seem to be able to get either the correct part or part number is somebody at KTM? Does this possibly have anything to do with the new shipping center? Why does Coop need 40 valve springs?

I really appriciate the fact that Mike Russo would call Thump to discuss the issue, but I do think that if user dstktmusa is a representative of KTM USA that they might have been better served by contacting Eric directly to discuss the matter. Often times some things are not clearly communicated through text and a phone call makes everything more focused. Then the resolution of that discussion could have been addressed here so that this mixmaster that the discussion seems to currently be in would not occur. also I think it would be a pretty cool idea if dstktmusa would arrange for the KTM rig to show up at Dirt Week 2003 with some representatives of the company and some bikes to interact with the end users and potential end users of their products. :)

 

[Thump]

Mike said he did not know who dstktmusa was speculated him being a KTM shop..? But he did say that he was correct with the numbers and such he was posting.

Coop didn't break all of them, but when they rebuild they rebuild everything broken or not.

 

[BCR-Bob]

Patman, one thing I should point out about my LC4 is that the cam was pretty big. As Mike Perry stated, the largest cam he knows of for the RFS has .413 lift. I should also state that I had to cut the guides down on the head to clear the retainer. Yes it was pushing the limits of the design, but thats where the fun is!

 

[SFO]

I would like to interject at this point that I consider valve spring replacement cheap insurance. Factory specs and service parameters such as lbs of pressure @ X installed height, free height, and parallelism do not take into account fatigue cycles. Even if the book doesn't reccommend replacement, if you have your head apart I would dump fresh springs in it.
I am just glad it is only 4 or 5 springs and not 16 or 20.
Spring failure can be epic and it is avoidable.
I wanted to see what mfg spring Bob was using so people would not confuse it with KMPI.

 

[marcusgunby]

 :whiner:

 

[Patman]

Originally posted by Thump
Mike said he did not know who dstktmusa was speculated him being a KTM shop..?

He may not know who but I'll venture it's NOT a dealer! dstktmusa has told me in the past he is a direct employee of KTM USA and I verified IS posting from their site... :think:

Perhaps Mike Russo would be interested in working some sort of official KTM USA technical support program out for the benifit of those on DRN?

 

[KTM-Lew]

Jeez! I go to work....spend a couple hours tracing a short on an Expolde-ition, diagnose a worn-out Power-Stroke, then spend 2.5 hours in a round-table discussion with a bunch of Ford engineer's trying to fix the 6.0L disaster to come home to this. I wish I had time to do all this research. :eek:

Guess what....I don't have to now. You guys did it for me. Thanks for the big spoon-ful of info. :)

Oh, somebody tell Jeremy to check this thread. I think he'll appreciate it. Sometimes you gotta stir the pot to make stew.

I have great respect for Eric. My problem was with the urgency that was indicated, and to me it seemed pretty clear that there was a mix-up somewhere. If I were going racing MX or desert I would be riding a Yamaha. For high RPM use a double over-head cam set-up is much more stable and less moving parts is allways more dependable. Having said that Ty Davis hasn't had much luck keeping his YZF's running so who's to say? For my use, trail riding and maybe a hare-scramble, my valve-springs will be fine. I have absolutely no concern for MY use. I'll say this AGAIN, if you rev your motor hard you need to take care of the valve-train. That means changing valve-springs about like you would do rings on a 250 2-stroke. Probably once a year on 400-520's would be fine for the hammer-head type rider. The 250f's are gonna be the problem children of the future. Too many people that have no concept of how to use the torquey power of the 4-stroke to the best advantage. They just keep riding like it's a 125 and then bitch cause the valves won't last a whole season. Ain't gonna happen.

As far as my experience with motors......35 years of turning bolts. Put a cam in a Briggs when I was 10. Been doing what was nec every since. Am I an "expert"? Maybe not. ASE Master Tech, A few classes short of Ford Senior Master Tech, get paid everyday for turning bolts. Suppose cars don't count?

Am I as knowledgable about current motorcycle technology as Eric? NO!
Do I think the RFS is a time-bomb? NO!
Am I happy to see this topic get this much attention?
Absolutely!!!!
The bikes we are riding are in most ways so much better than what we once had but they aren't maintance free. They aren't an XR!!! How fast can you afford to go? Speed (RPM) costs money.

Hope that's clear enough. :yeehaw:

 

[EricGorr]

The thread I started regarding the KTM valve train issues has raised some controversy and peoples’ blood pressure. People have suggested that I’m incompetent at basic tasks like looking up correct part numbers. Here is some background information on what led up to the thread.

Last autumn, one of my customers had a top end failure with a 2000 400SX. I went to my local dealer Barr’s KTM in Madison and ordered replacement parts. After 32 years in the motorcycle industry I know how to read a parts card. The suggestion that I was mistakenly reading a 2003 card rather than a 2000 is impossible because the dealer didn’t as yet have the 2003 parts cards in stock. I ordered all the valve train parts including a head. After three months on back-order, the parts started trickling in. Steve Barr’s son races a 400SX and their mechanics are keen performance technicians. When replacement parts are different in design than older parts we share information, discussing how the improvements will work with existing parts. We pride ourselves on being consciences technicians. When we received the conical springs we immediately questioned KTM, explaining that we ordered parts for a 2000 model not a 2003. A person in the parts department at KTM in Ohio told us “the conical springs are the updated part number, you get these when you order the old number”. We examined the cylinder head dimensions and immediately noticed that the spring seat diameter on the head was smaller than the diameter of the bottom spring seat for the spring. Barr’s was in the process of updating their own race bike and we figured that we’d have to bore the spring seat larger to accommodate the new conical spring. We both machined our heads accordingly. My biggest concern is that if the average guy orders these parts and fits them to their old head without doing the machining, the springs will be under greater preload and a failure will occur. I was also concerned that KTM didn’t put any written communication in the box for the spring warning about the need to re-machine the old heads. In fact that’s really what the heart of this whole problem is, a lack of communication on KTM’s part with regards to parts updates and service issues. Their newsletter features blibs about their sales outings but nothing about service updates, recalls, tech tips. Do they have any representatives browsing technical forums like the ones on DRN? I’ve never seen anyone in an official capacity from KTM out here or on Thumpertalk.

My suggestion that KTM has some problems with wear on valve train parts is backed up with observations and actual service on KTMs and Japanese four-stroke engines. Just this week, two of my friends who own 2000 KTM520SX models disassembled their engines as part of their annual maintenance. Both bikes have severely worn intake valves and guides, one bike has about 40hrs. and the other has over 100hrs. of run time. The two individuals are +45 vet experts, Fritz Heubner and Jim Webber. Both of these guys are accomplished mechanics and conservative riders who understand how to maintain a four-stroke. Fritz is a former factory mechanic working for Yamaha and Bultaco in the 1970s. His job is to restore and maintain a stable of vintage racecars for Bill Jacob, a wealthy auto dealer in the Chicago area. Jim is renowned for his Maico restorations and works in the motorcycle industry for Bell Industries. Jim’s bike was the biggest surprise for me, because I rode it on the ice recently and it didn’t display the typical symptoms associated with “cupped” intake valves. The bike started fine, didn’t tick or fart at idle, and the power was what I expected. I’m guessing that if I can be so easily fooled by a bike, there are a lot of you guys that wouldn’t have a clue that their bikes are headed for a major engine failure.
These two bikes that I described are minor in comparison to some of the engine failures that I’ve seen when worn valve train parts are allowed to go too long without service.

The whole point of my original thread was to make you guys aware that you need to do some maintenance on four-stroke engines. With more moving parts than two-stroke engines its ludicrous to think that four-stroke engines are as maintenance free as the popular press has pronounced them to be.

As far as tips on replacement parts are concerned, I recommend Kibblewhite valves, springs, and retainers. The telephone number of Kibblewhite in Pacifica California is (650) 359-4704 and the part numbers for the intake valves are 96-96007 exhaust valves 96-96004 and the springs/retainers kit is 96-000 Find a qualified technician to check the condition of the valve seats before installing new valves. A good valve job will go a long way towards protecting the new valve train parts.

PS don’t expect to see me answering questions in this thread anymore because I’ve said my piece and that’s all that needs to be said. I’ve got the seasonal glut of performance work to deal with in my shop right now and that demands all of my attention. If the usual suspects want to take potshots at me again calling me incompetent and an imposter then so be it. I’m just going to ignore those %&#(^>s because it takes two to argue.