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Only $10 for all 2024 SX, MX, and SMX series (regularly $30).
So why is the bracket brazed and the pipe welded? Because the pipe is a butt weld, they actually torch weld with a flame all the pipe halfs, using no filler metal, its faster and has a lot of control in thinner metals. The bracket is a lap weld, filler is required for the required strength in that braze joint.
In short, its a issue of speed and convenience.
Decided to rework the original brake stop, moving on..
That's all for the frame modifications. Time to tear it down and off to powder coat.
The Shop
I sure wish those blue anodized forks were staying. They look so badass.
The motor was suppose be "ready" but by the looks of everything else i've put my hands on, I had to crack it open.
As you can see the impeller drive gear on the end of the crank shaft was beat to death, mushroomed and had broken teeth.
At first I thought the rod bearing was bad, but I think it will make another run.
Had to make a few tools to get this gear off....
I overlooked the Blue Moon Belgian White... SO GOOD!!
The frame looked great!!
Congratulations on the tool making to get that shaft out.
As I was reading your build I wondered if I knew who you were, once I saw the slide hammer on the drive gear I started laughing cause I realized who you are.
I like the mods you are doing.
The Brembo brakes are going to be awesome.
I did a KX450F Rear brake and wheel conversion on a K5 and it made a HUGE difference.
The Pro rider who runs it use to literally burn his K5 rear brake up after a few laps.
He has rode it for several races and no issues and absolutely loves it ... So, I'm sure that you'll be happy.
I like your approach for the forks as well.
You should have a real nice bike when you are done.
Congrats!
I have never rode a K5 but only 3 min around my yard with a bald tire. But one thing I gathered from various sources was brakes = junk and the chassis/suspension isn't up to par.
The brake conversion I knew for me was going to be easy, plus I had extra set of brembos, kinda a no brainer.
I'm going to give this shock a good rebuild and try, being that shock designs haven't really changed much in 30 years, I do think I'll be able to get it working decent with the Race Tech stuff. Might look into the emig racing dog bones as well.
Forks, if in question during any build, 06 - up KYB SSS. Bone stock and sprung are just so good.
It"s a 90.....I have been thinking about what to do with the fork upgrade. Originally was just going to put the latest k5 front end on, from 99-2004 for something easy...but I see a nice looking set of Pro Circuit clamps on eBay from a late model 250f.....which would be same swap you have done....appears you used the original k5 stem, was this due to height of stem or bearing size? Also, when you had the head decompression mod done, was anything else done to the head? Squish ect? Thanks...
Pit Row
The front end. I had a yamaha set of forks from my 13 300sx I sold a few months ago, that's why I went yamaha, but you would probably be better off finding the SSS forks used on the KX450 a few years. The bottom fork diameter is the same , but you will see different top clamp sizes depending on the year. BUT! no worries, you can send your trees to Clayton @ Trick Engineering and he can bore to fit for about 50 bucks (that's what I did).
The top bearing on the K5 is smaller and doesn't fit any modern clamps that I know of. That is why I used the steering stem to avoid major frame modifications. But after retro fitting the trees to work with the small top bearing, I believe its about the same amount of work to cut out the top frame cup and weld in a new cup to fit the bigger bearing race. With my resources and had to do it over, that's what I would have done. Because if you wanted to change the trees later maybe to try different offset or whatever, would be nothing to it. Now if you need help on the frame modification part, contact me directly and I can handle it for you.
The compression release was done by Larry Wiechman wiechman@charter.net
Excellent work, he cleaned up the head, installed the comp release and polished the combustion area. The squish will vary from bike to bike depending on a lot of factors. I can handle that on my end. But he might be able to get you dialed, give him a shout.
On the steering stem, you can use a 450F triple clamp on your older KX by pressing in a new stem from EMIG racing.
I believe they are about 100 USD.
If your getting ready to rebuild your K5 engine here is some tips that I put together that can help you get a little more performance out of it..
Did I mention washing it first? Lol..
If so, I'm pretty sure they are the same from 97-04 when they switched to their final fork design.
Or did I completely miss something?
The shit sucks. Apparently at some point the motor fail and something was wedged at the bottom the case causing it to scar and bulge. I'll take a stab in the dark and assume the same guy that greased the bearings tried to pull the gap in with the case bolts. This caused one of the tabs to crack.
I've started the repair. We'll see what we got after I weld the tab back right and try to lap the cases flat.
Some good news, the blind trans bearing is out easy. My graphics are done and in, look real clean and simple. In Jan I hope to be moving forward pretty good.
Here is the basics:
Unlike other lapping compounds, Timesaver Lapping Compounds do not contain emery, silicon carbide, aluminum oxide or similar permanent charging abrasives. It will not charge into any metal surface or continue to cut. The lapping compound has a cutting action that is rapid at first and gradually diminishes as the abrasive particles disintegrate into inoperative material. The finishing action is such that surface irregularities and surplus metal is gently and quickly removed without disturbing the natural metal structure.
Timesaver Lapping Compound is manufactured expressly for the purpose of fitting and smoothing the bearing or contacting surfaces of rotating, oscillating or sliding parts of a mechanism. Assembly lapping of parts with Timesaver Lapping Compound, regardless of shape, size or the part involved, will result in precision fits, proper oil clearance and a microscopically fine finish.
Timesaver Lapping Compound cannot replace all of the other lapping compounds available, but if you are hand fitting pieces, have a hot bearing, gear noise or other demanding application where complete disassembly is not desirable, Timesaver Lapping Compounds may be the answer.
RECOMMENDED FOR : Fitting babbit bearing, brass valves, bronze bushings, bronze worm gears, fitting brass, babbitt and other soft metal guides, cooling down hot journal bearings without disassembly and similar uses.
Your cases are bad enough that I would start with 40N Coarse then finish it out with the 100N Very Fine.
This is a typical area that needs to be lapped on every set of KX500 cases I have ever done..
Have fun... I've done a huge pile of them over the years :-)
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