KX500 gearbox problem

**scott411** · 11th August 2010, 08:57

Originally Posted by brp

True

What makes the suspension , frame, so much better on the latest mx bikes compared to a kx500 ?

20 years of devolpment basically, its like comparing an 89 ZX10 to the latest ZX10R

the KX500 is very soft, and sits low in the stroke, you sit in the seat rather on top of the bike, the weight is very high in the frame, modern bikes turn much better,

**brp** · 11th August 2010, 11:06

Cheers

Looking forward to dialling in the suspension on the 500, impressed with it as it is (been set up for a short rider). Find traction good to by hooking through the gears quick, no powerband , nice control.

As four the 2 stroke vs 4 stroke discussion - think when they made 125 2 strokes race against 250 4 strokes and 250/450 it said it all !

Picking once the VMX class moves from 86 to 1990 - the $3000 KX500's won't be seen anymore on trade me.

**scott411** · 11th August 2010, 12:11

Originally Posted by brp

Cheers

Looking forward to dialling in the suspension on the 500, impressed with it as it is (been set up for a short rider). Find traction good to by hooking through the gears quick, no powerband , nice control.

As four the 2 stroke vs 4 stroke discussion - think when they made 125 2 strokes race against 250 4 strokes and 250/450 it said it all !

Picking once the VMX class moves from 86 to 1990 - the $3000 KX500's won't be seen anymore on trade me.

flywheels weights help alot on KX500's, i also used to start in 3rd gear with standard gearing, if you have the room you will still get holeshots with ease

**cs363** · 11th August 2010, 19:26

Originally Posted by scott411

flywheels weights help alot on KX500's, i also used to start in 3rd gear with standard gearing, if you have the room you will still get holeshots with ease

Didn't that KX500 bite you rather hard Scott?

**Crasherfromwayback** · 11th August 2010, 19:31

They tend to do that!

**scott411** · 11th August 2010, 21:04

Originally Posted by cs363

Didn't that KX500 bite you rather hard Scott?

never had a big one on the 500 there Colin, it was the 125 a few weeks later that bit me pretty good,

but your getting old in years, so i can understand why your memory is fading,

**CHOPPA** · 12th August 2010, 13:46

Originally Posted by scott411

flywheels weights help alot on KX500's, i also used to start in 3rd gear with standard gearing, if you have the room you will still get holeshots with ease

So i prob shouldnt have lightened mine??

I think the problem with the big end came from running castrol r instead of decent synthetic oil

**Crasherfromwayback** · 12th August 2010, 14:27

Originally Posted by CHOPPA

So i prob shouldnt have lightened mine??

I think the problem with the big end came from running castrol r instead of decent synthetic oil

They stall too easily if you don't have enough weight on them, it also makes the traction situation even worse.

I wouldn't be surprised if that oil was at least half the problem too.

**CHOPPA** · 12th August 2010, 14:57

Originally Posted by Crasherfromwayback

They stall too easily if you don't have enough weight on them, it also makes the traction situation even worse.

I wouldn't be surprised if that oil was at least half the problem too.

Ill just run the idle high i guess

**Crasherfromwayback** · 12th August 2010, 15:06

Originally Posted by CHOPPA

Ill just run the idle high i guess

And that's not a bad thing on one of those beasts. Stops them going BING BING BING and firing you over the top of all the berms!

**CHOPPA** · 12th August 2010, 17:09

Cant wait to get it out on a maize paddock or sand track (at the start of the day)

**Blagger** · 12th August 2010, 18:12

Hey crasher, I take it that your comments re KX500s would also run true for CR500s of a similar vintage?

My mate rides one and even when he's got it running on song my 4 stroker hauls him in on the straights pretty easy - but then I'm a fairly crap rider and he's just plain loopy but that's another story

**sugilite:Me** · 12th August 2010, 18:37

Originally Posted by Crasherfromwayback

All three of my RMZ450's would wheelstand in top with std gearing. The 2010 model with real ease. The 05 4 speed topped out at around 70mph, and a KX500 on std gearing not much more. They (KX500's) only rev to 7500rpm, where as a 450 four stroke will rev to 11000rpm.

Your KX might feel like it's doing 150kph...but it ain't if you're running std sprockets. When I was road racing KX500's...I had to run 16/36 to get them to pull 180 kph. The 2010 RMZ450 I had, would pull the same speeds with a 15/38 combination no sweat.

Shit, only 180? I ran that gearing on your old bike and was passing f3 bikes down the straights at manfield, not the fastest f3 bikes though. I did a 1:18 flat in 2004 with a SHITTY wiseco piston, wont do that again. It was def slower than a standard piston, so quite sure getting into the 17's is possible on a 500 with standard forks n shock. I don't think the 4 stroke brigade got into that territory at manfield till last year? I do remember looking down at the forks on one of those laps in the sweeper, holy fuck, they were flexing around like soggy pasta, I won't be looking at those again

The 450's are definitely easier to ride though, at least it looked that way to me when I was lying on the ground seeing you dissapear into the distance at that upper hutt race....TWICE!

Personally, I like the challenge of riding a 500, having a bike that is looking for the slightest excuse to fuck you up is good fun