2008 KTM 450 SX-F

[RockChucker]

Figured I would post this here as a long shot. A few months back I picked up an 08 KTM 450 SX-F with a bad motor for $500. The cylinder was salvageable and I had Lindsay Machine Racing send it out for a clean up and replating. The valve guides were toast, as were the exhaust valves. Intake valves were good. I had LMR do a valve job while I waited for the cylinder to make it back from plating. This last week, I've been getting the motor put back together with a new Wiseco piston. The motor is completely buttoned up, but I need different valve shims to get the correct valve lash. I'm planning on selling this bike when it is done and don't want to drop ~$60-70 on a full shim kit. On 3 of the valves, I have what amounts to zero lash, so I don't know exactly what I need. Thinner than what I have though . Does anyone have an assortment of 8.9 mm diameter valve shims that I can play with to set the lash right and then buy what I need from you? I'll buy a kit if I have to, but would like to avoid it if possible. Thanks.

 

[anderson750]

That bike has 2 strokes more than you will find most of us having any parts for. if you dont have any luck here you could join a Facebook group called Desert Flash and ask on there

 

[rholbrook]

I have a bunch for Yamaha but not KTM 4 strokes. Most of the extra shims poking around would be replacements anyway and probably not what you would need.

 

[RockChucker]

That bike has 2 strokes more than you will find most of us having any parts for. if you dont have any luck here you could join a Facebook group called Desert Flash and ask on there

Ha. Figured it was a long shot. No sweat. I'll track some down.

I have a bunch for Yamaha but not KTM 4 strokes. Most of the extra shims poking around would be replacements anyway and probably not what you would need.

No worries.

 

[Gravy]

You can order individual shims online.
Also most shops will just sell you individual shims for like $4/per
I've got some but I'm not around for a minute.


Also if you or anyone else needs cylinder replating, message me. I've got an account with Millenium Technologies Replating and I'll only charge a few bucks over cost instead of the $100+ overcharge LMR does

 

[RockChucker]

You can order individual shims online.
Also most shops will just sell you individual shims for like $4/per
I've got some but I'm not around for a minute.


Also if you or anyone else needs cylinder replating, message me. I've got an account with Millenium Technologies Replating and I'll only charge a few bucks over cost instead of the $100+ overcharge LMR does

Good to know about the plating. I think I paid like $285. It seemed steep to me, but still way cheaper than a nearly $1000 cylinder new. I know you can buy individuals. Problem is 3 out of the 4 shims are too tight and I can't get a feeler gauge in at all, so I'm not sure what sizes I need. Tonight I'm going to move the thinnest one around and see if I can estimate what I might need.

 

[2002maniac]

I was once in this situation and was able to lap the shims down to get the proper clearance. It was kind of time consuming since the shim material is very hard, but it did work.

 

[Gravy]

You can stick some 1000 grit to a piece of glass and wet sand a shim down a few thou at a time.
Your shims if new should never be that tight however. 4 stroke valves get tighter as they age because the valve both stretches and sinks into the valve seat as it wears. New valves should have loads of clearance.

 

[Gravy]

Just between us I don't like LMR for 4 stroke top ends. I wouldn't trust that they did it right if you have zero lash.

 

[Gravy]

Also. You need a set of bent motorcycle specific feeler gauges. Automotive ones are usually too wide and cumbersome and too thick to check tight clearances, so that's a possibility.

 

[Caleb]

I doubt they’re the right size but I have a full set from one of my bikes I’ll have to find them and I’ll check what size they are. If they are the correct size you are welcome to have what you need.

 

[RockChucker]

Just between us I don't like LMR for 4 stroke top ends. I wouldn't trust that they did it right if you have zero lash.

I don't have a problem with the work they did. Although it was pricey. Still cheaper than the edge motorsports at the point of the mountain in draper though. I'm not surprised the original shims didn't work. They installed new valves. Honestly I would have been shocked if the original shims did work. I ended up needing shims roughly 0.2mm thinner for all 4 valves. I broke down and bought single shims from the edge at $9 each. Faster and cheaper than ordering a full kit. But still ridiculous. The lash is on the loose end of spec now. I should get the bike assembled in the next couple days and hopefully sold within the next couple weeks. Can't wait to wave good bye to it.

 

[anderson750]

I broke down and bought single shims from the edge at $9 each. Faster and cheaper than ordering a full kit. But still ridiculous

If they are OEM, then that is what you would pay at any dealership. The parts counter is where dealerships have the most margin.

 

[RockChucker]

If they are OEM, then that is what you would pay at any dealership. The parts counter is where dealerships have the most margin.

I suspect they weren't, since all of them were .02-.04 mm thinner than the number marked on them.

 

[Caleb]

Man, at $9 a piece, a hotcams full shim kit is only $50.

 

[glockman]

I have hot cams kits for both sizes. You are welcome to what you need. I can bring them to work Wednesday.

 

[RockChucker]

I have hot cams kits for both sizes. You are welcome to what you need. I can bring them to work Wednesday.

I got it all back together. The bike is about 90% assembled now. Hoping to fire it up tomorrow night after work after I charge the battery and fill up fluids and do a final bolt check.

Man, at $9 a piece, a hotcams full shim kit is only $50.

I wrestled with getting a whole kit, there is a Wiseco one on amazon for about $38. But ultimately it was faster to just go pay an obscene amount for the ones I got haha.

 

[Gravy]

Sorry I guess I was confused, I didn't realize you were measuring your lash with the shims you already had in there.

When you said zero lash I was assuming you were measuring without shims in to get your baseline.

It is my experience, however, that new valves will require a thicker shim than what is usually in the bike before the valve change - as it's unlikely that a valve change is required until the valves have been adjusted 3+ times. So usually the shim is thinner than stock, so when new valves go in you'll generally need a thicker valve shim. Clear as mud?

Unless they just recut the valve seats (which sinks the valve in the head and does require a thinner shim as the valve stem moves physically up)... Instead of replacing them...

Did you go with an OEM titanium valve or stainless?

 

[RockChucker]

Sorry I guess I was confused, I didn't realize you were measuring your lash with the shims you already had in there.

When you said zero lash I was assuming you were measuring without shims in to get your baseline.

It is my experience, however, that new valves will require a thicker shim than what is usually in the bike before the valve change - as it's unlikely that a valve change is required until the valves have been adjusted 3+ times. So usually the shim is thinner than stock, so when new valves go in you'll generally need a thicker valve shim. Clear as mud?

Unless they just recut the valve seats (which sinks the valve in the head and does require a thinner shim as the valve stem moves physically up)... Instead of replacing them...

Did you go with an OEM titanium valve or stainless?

OEM valves from KTM. They recut the valve seats and installed new guides/seals. I think the stems moved up, which is why I needed thinner shims. I wasn't terribly surprised I needed thinner ones.