Brutes 2000 KX5 Street SuMo Build

[Sandblaster]

Ran it up and down the local Highway for a bit this morning and did a plug color check. All good. Light/medium brown. Could be a little lighter, but not dark enough for 'lazy' me to want to change jets. smiley Had the stuff sitting on the bench to put the Oxy probe in the pipe but think I will bag that as the plug color is pretty close.
Took it on a 30 mile ride combined freeway and secondary roads. Interesting how much more noticeable the 'run on' is on the street! The power pops on a single 500 are fairly dramatic on deceleration. Would be an unwelcome surprise on a 'pushing the limits' corner.
I happened to be looking into my left hand mirror about the time it snapped off at the base and vacated the bike while on a freeway run. Little vibration on it at speed in certain RPM ranges.
Max temp (Lugging a bit on a long hill) was 210. Average was in the high 180's/low 190's. Speedo says the max speed reached was 93.8. Probably from rolling on the throttle at the freeway on ramp to merge. Builds speed quickly the higher the RPM gets. Lot's of grunt down low too!
Only killed it three times at lights. tongue There is a fine line between a smooth start and doing a wheelie as the power starts to climb pretty hard at about 3000-3500 RPM. Found short shifting made it much smoother.
All in all I am happy with the conversion. Got lots of looks and thumbs up. There are tunnels under SeaTac Airport and it sounded great going through there.

Foxx4Beaver
nice!...I'd love to hear a 500 on the pipe going through a tunnel!

sandblaster
To help smoothen out the hit I geared mine pretty high.
Requires a bit of clutch to take off in first but isn't to hard on things.
I still have not tapped mine out on top end but I suspect it should do about 100 or so as it does mid 80's in 4th gear..
I have a lot of guys giving me the thumbs up when they catch me at a stop light shocked
Better ride it all you can while the weather is cooperating

Brute
15/43 on mine. Slip the clutch a bit with a gentle touch on the throttle. shocked Likes to accelerate! evil Does not care for steady cruise so much. DaaaaDaDaDaDaaaaDaDa undecided 5th gear roll on is impressive once the revs start climbing. Went by 2 cops with just a glance.

sandblaster
DaaaaDaDaDaDaaaaDaDa
Mine does the same thing while at steady cruise unless I'm going about 75+
Did you open up the size of your vent tube on your gas cap?
That helped mine a bit but didn't cure it.
Trying to get the MZB on this week to see if that will help.

Brute
Just let my friend 'the racer' ride the KX5. He owned and rode 2 strokes before. HUGE grin. Loved it. Was sad he did not have his leathers with him. I imagine all the cops in the area will be looking for it now... grin I would like to see him wring it out on a track.

So to back up just a bit, was going to leave the bike home yesterday as the replacement mirror had not arrived yet. Got it an hour before work, stuck it on and did the 14 miles to work and back.
Just took it out to verify and correct the speedo to a GPS. About seven miles total ride. Was going to ride it to the Post Office. Pulled out of the driveway and, the left mirror broke off at the same place the other one did. About the same total miles on it too. Sharp corner they left at the base does not like KX5 vibration me thinks.
When I was driving it in to work yesterday I reached out and compared felt vibrations between left and right mirror stems. Left was noticeably higher. Presume it is because the master cylinder cancels out some on the right. Got to do something different. Thinking bar ends.
Fifth starts running out of steam at just over 90 (on a closed course, of course...) but I think if I geared it a bit more to keep it in the 'sweet' zone it would go faster, not that I need to.
Pushed it on a couple corners and it is stable and, well, pretty fun! Still do not like the 'run-on' but that is the nature of the beast.
Lugging it below the hit at about 4K makes it smoother on the corner and if I time it right it is hitting the power as I am coming out of the corner.
Man it plus hard when it clears it's throat and gets down to business!

Just found out one of our janitors was having a cigarette at one our buildings on a corner on the other side of the field. Appears my KX5 came around the corner flat track style and smoked the tire accelerating down the straight section of the road after the corner... No wonder "the racer" was grinning when he came back! All I had told him was "Don't get hurt".

[Sandblaster]

BRUTES 2000 KX500 SUMO BUILD 9-91.jpg (952.48 KiB) Viewed 3491 times

Latest look with rubber mounted bar end mirrors. So far so good with the rubber inserted bar ends. Had to bore out the ends of the extra thick aluminum bar to make them work but if they do not leave or break off the bike I will be happy.
Got to say, this thing pulls so hard in 5th at 90+ mph I am surprised the speed record is only in the 125 range. There is much more to it I understand, wind, traction and such, but still, seems to have plenty of power up there. I am at 15/43 and would maybe go 39 if I end up taking it to the track.

sandblaster
Lookin good.
Someone needs to break the record...
There is all the knowledge and experience here to do it..
I've got a frame and a few other parts to donate to any serious attempt on this site...

Brute
I suppose the weight is one thing. When I was at ElMirage once I was surprised at a Chevelle that was over 7000 lbs. saw the bolted in lead blocks and asked. Salt or sand ain't asphalt!

sandblaster
I do a lot of reloading and can send some lead as well

Brute
Anyone know what the speed record KX weighed?

[Sandblaster]

As some of you know, I bought Brutes SM about 6 months ago or so...
I've been so busy I have not had time to ride it but once.
Jason has been drueling all over it since I bought it so I've been letting him ride it...

https://www.youtube.com/watch?v=RlxbSRB_v1g

[Sandblaster]

I forgot to mention that before we rode it, we changed the oil, cleaned the filter, checked the jetting, set the floats, and generally cleaned up the carb a bit

Before

www.kxguru.com kx500 carb clean 101.JPG (158.89 KiB) Viewed 3200 times

After

www.kxguru.com kx500 carb clean 102.JPG (247.85 KiB) Viewed 3200 times