1999 KX500 from scratch

[grippy61]

New to this forum, and it is full of info. I have a 1999 frame that I bought off ebay in great shape, with a title.  I couldn't find a clean complete bike with a title in my area so I figured I'd build it.  So I've started with used frame, new cases, used forks, and used swing arm.  I want to build it with a mix of new parts, used and aftermarket parts.  What I was hoping to find out is what parts should I consider going with aftermarket, like electrical, transmission or wheels and hubs.  I've never really done anything far from stock on a bike, as my 1985 KX500 is bone stock right to the handle bars.  Any suggestions would be great, and when I figure out how to post pics I'll do it.  Looking at a Clark fuel cell right now, stock size?

[lsampson]

New to the site too, but welcome! As far as what parts to go aftermarket, Fenders and seat cover, unless you like the purple seat . Also, Sprockets and chain as a no brainer. I've always like renthal sprockets and chains. Also, a Renthal bar. The rest is pretty solid as far as OEM goes!

[Ims Roll]

tm chain rollers will help from eating your sub frame in half. For me personally i made a mud flap out of some heavy rubber used to line the bottoms of tool boxes, lasts longer then a plastic one and will save your rear shock shaft. Also heres a link to an easy yet useful mod, http://www.kxriders.com/forums/index.php/topic,5846.0.html   


welcome and good luck, there are all kinds of cool things on this site from easy to do mods and lots of helpful tips to making your K5 build easier.

[grippy61]

Just finished welding and cleaning the frame before powder coat, nothing major just a small crack on the sub-frame mount.  Has any one used a sub-frame from AC racing, going to order it today.  Looks like to be a good part, they say its stronger than the factory one.  Getting ready to do the suspension.  I am using factory 1999 forks with RBP triple clamps.  For the rear I'm thinking about going with Ohlins shock.  Where can I find hubs and wheels?  Machined hubs ,what have you used or seen others use.       

[alward25]

Just finished welding and cleaning the frame before powder coat, nothing major just a small crack on the sub-frame mount.  Has any one used a sub-frame from AC racing, going to order it today.  Looks like to be a good part, they say its stronger than the factory one.  Getting ready to do the suspension.  I am using factory 1999 forks with RBP triple clamps.  For the rear I'm thinking about going with Ohlins shock.  Where can I find hubs and wheels?  Machined hubs ,what have you used or seen others use.       

You could put a KX 450 front end on it and get a steering stem from Emig racing.  Warp 9 is as tough as anything out there, been beating mine for a long time.  They sell them for the K5.  You can use a KX 450 rear wheel but you need the warp 9 adaptors or make them if you have some lathe skills and a rotor from them too.  Or turn down a 450 rotor.

[grippy61]

award25, Thanks for that info on the warp 9 wheels and the Emig clamps.   What  is the benefit of the 450 forks over the pair I have?   Haven't made the purchase for the clamps yet.  Is the performance in the fork or the adjustability of the Emig clamp? 

[alward25]

You use the stock KX clamps with the emig steering stemm to adapt them to run on the KX 500.  The 450 forks are a twin chamber fork. The clamps have a different offset, Motoraad, what are they again?  You also update to a newer front end so you can run a KX 450 front wheel, the fork guard look better.  You can also get a set of super too wheels with the oversized front rotor because I have not seen anybody that makes one for the K5 front end.  Just newer over all, you could sell your forks for $100-$150 and buy a 450 set for about $200. A set of clamps are about $50 top and bottom and I think the stem is about $100.  A few guys on here have done it and really notice a difference.  Any of them could do a better review.

Alex

[ID KX500]

The KX500 front-end bolts right on to a KDX200/220, so if a KDX owner was looking for a swap it could sell.

[alward25]

and who would not want an upgrade.  Way to go Id-a-ho that was my daily cheese and now back to your regular scheduled programming

The KX500 front-end bolts right on to a KDX200/220, so if a KDX owner was looking for a swap it could sell.

[Goat]

Welcome to the site. What type of riding do you plan to do with this bike?

89-04 transmissions are pretty close to identical. Just minor gearing changes over the years and the shift shaft is stronger from 95-04 than previous years. I do believe there is still an overdrive kit available for the 500 as well. I don't recall who on here was making them though.

90-04 electrical is all the same. If you're wanting to run lights there are a couple options but by the looks of it only 1 is worth it. MZB ignition. It is in the commercially available services on this site.

Clark fuel cell's are nice. If you like to ride for long periods away from a fuel station I would recommend a larger tank though. They like their fuel more than the older bikes lol.

Warp 9 is superior IMO when it comes to hubs and wheels. I've had excell and destroyed most of the wheels in 1 season.

I prefer All Balls bearings and seals but everyone has their preference. Boss Bearing is a good company as well.

Jfabmotorsports has windowed Wiseco pistons for stock 86mm bore. Adds 3hp and runs cooler than stock piston. Also in the commercially available services.

[grippy61]

It will be mostly a closed course bike, but the places I go are very different.  One is different every time I go, if it's dry the track is knee deep sand, if wet it's like knee deep sand that sticks to you.  I also go to a lot of local motocross tracks, off road parks, and friend lands.  Looking for public land to ride.                                                                                                                                                                                                                                                                                                                                                  Thanks for all the info. I'm going to get a set of the warp9 wheels, seems to be a favorite.     

[Goat]

I would definitely go with the 450 suspension for motocross riding. I've ridin a 450 even though I hate thumpers the suspension is awesome. The 500 suspension is outdated. It can be rebuilt to be better than stock but still doesn't compare to suspension off a newer bike. Like the difference between cadilac sts and a chevette lol. Maybe not that drastic.

Personally I would go with a Pro Circuit pipe. FMF is good for woods and desert but lacks on a track(2 different pipes though). The PC pipe felt perfect when I rode mine on the track. I've never had one of those fancy pipes like zip ty so I cannot comment on that.

[grippy61]

Goat, Thanks for the info on the suspension. Not a fan of the four strokes either, but they are good for testing suspension.   Started looking for forks this morning.  Frame is back from powder coat, looks great.  Swing arm I had dropped off to fill some holes drilled in it for a kick stand and they are going to do a brushed finish on it.  I like Pro Circuit pipes, that's what is on my 85 500.  Whats the deal with the zip ty pipes never seen anyone with one, on anything.   

[Goat]

There are quite a few guys running the zip ty pipes on here. Hopefully they will comment.

Kick stands are nice if you have solid ground to park them. I usually just bury the back tire lol

Must post pics!!!  Everyone here loves pictures :D

[Ims Roll]

Welcome bud.

Not to reject anyones opinion but personally have had 2 rear warp 9 wheels explode and also have had a buddy destroy a warp 9 rear




Good luck with your project