Found the Second Sweet Spot!!

[Jeb]

Oh how thrilling . . .

The rain they called for never happened today. So we loaded up the bikes and headed out to Bucks Run Motopark. Rode both tracks then through some woods but very sloppy from the rain (tough on a youngin' getting used to his race bike), so back to the tracks.

He rode, I fiddled and fiddled with the A/S from 2.25 - 2.75 out. Actually I found a couple of spots with improved performance in different ways, but 1) it wasn't hugely different than the other places in that range and 2) the bike didn't run poorly in at the other places in that range (some of the threads I read this past week indicated that the SSS was very obvious).

So for giggles I raised the needle one slot (#4, CEK). Uggg, performance was markedly poorer. So I tweaked a few times and was close to going back to #3 when things got LIVELY at 2 & 5/16 out (I had actually passed over this spot within the previous 20 minutes or so). SON!!! It was like I went and changed something more drastic than just a sliver of a turn on an airscrew!

Then I remembered the whole 3rd gear uphill 4-stroke thing, so I rode (actually, I zipped) out back into the woods and found me a good uphill. And JUST like has been described by others, as you start bogging you cut the throttle back (it was a bit tense the first time because I wondered if I would stall) and - "you gotta be kidding" was the first thought. The bike continued up this fairly good hill and never died. I did it again and didn't hit the hill as fast and - same thing! Except this time I let it ride at lower RPMs. The RPMs were low enough that it sounded like it was getting ready to shudder and die, and still it went. Good Golly Miss Molly!!!

So I hurried back to the tracks (which was easy to do!) - Brandon's on the PeeWee track. No one else is there, so I ease in and opened her up heading towards some whoops (granted, they weren't exactly giant whoops, but plenty big enough to have some fun). When I juiced the throttle the power actually surprised me, caught me off-guard, and went over the first whoop on the back wheel. And then the next whoop. And then the next . . . I finally regained my senses and cut the throttle back and rode out the last whoops but was skimming em' pretty good. WOW!

My point about the whoops is actually twofold - RB power AND USD forks.

My 220 rips!! If you don't have this mod YOU ARE MISSING OUT!! GET IT - NOW!! Before the summer comes!!

Many thanks to all you KDX guys for the suggestions, comments, tips, etc. And many thanks to Ron Black way over there in beautiful Oregon for a FIRST-RATE service.

[Indawoods]

The hidden 4 stroke... gotta love it!

[bradf]

Ron should send a pair of depends with the mod.

That SSS will change "slightly" when the temps change. For me it is about 1/32 turn for each 10 degrees. When it is slightly rich I'll hear a decel crackle in the first few inches of the pipe when the throttle is chopped. When it is lean it will have a slight hesitation bog in the 3rd gear quick throttle roll on.

[Mr. Wibbens]

I showed a guy yesturday how the RB mod is on my bike

I took off from a dead stop, slight uphill, in third gear and before the rpms climbed any higher than the ol' BOOOOOAHHHHHH! I shifted through the gears. 4th and 5th pulled no problem, but had to feather the clutch when I hit 6th

He was quite impressed

[Jeb]

Ron should send a pair of depends with the mod.

That SSS will change "slightly" when the temps change. For me it is about 1/32 turn for each 10 degrees. When it is slightly rich I'll hear a decel crackle in the first few inches of the pipe when the throttle is chopped. When it is lean it will have a slight hesitation bog in the 3rd gear quick throttle roll on.

Thanks for the feedback.

Don't laugh but . . .

do these micro-adjustments work to lean/richen things in the "standard" way for this "non-standard" modification, i.e. temps warm up therefore the carb runs richer therefore A/S is adjusted out(and vice-versa when temps get cooler)?

[bradf]

yep. The AS works exactly the same as a non-RB mod. It is still an AS.

[canyncarvr]

Re: '..the same.'

That's not my experience. In the SSS zone, colder temps mean the AS comes out more, not less. Opposite, likewise. Warms up? AS goes in.

I'm talking about changes a total of 1/8th turn or so and that in the 2.75 +/- range. ...more or less. I know it's there, I just FIND it!

Do it most every ride during the ride. As predictable as gravity.

The SSS has to do as much with fuel delivery as air..that due to pilot circuit modifications done.

IMO and all that. If that take is incorrect, it's odd then that it is repeatable without fail, with complete consistency.

My carb is a 4-vent. The two (OEM small body PWK and air striker) are NOT the same animal.


Jeb: Reading your post I must admit I would wonder at your enthusiasm over a simple air screw adjustment...if I didn't know that it worked exactly that way....in spades!

Fun, huh?


Saturday's ride was such a treat!! And that largely due to Ron's work. We rode 'backwards' over a few tracks..uphill over a few well-rooted spots. What complete machine satisfaction from the 'lil green machine. Power! Well applied! Well suspendered!

YeEHaW!!

Anyway...good to hear you took the time to find it. It's easy to pass up, ain't it.

Thanks for the post!! It's great to hear about it when things work!!

BTW...as far as beyootiful orygone: When 'ya coming out for a ride? Soon, right? Another 'can't miss it' guaranteed!!!

[Mr. Wibbens]

My carb is a 4-vent. The two (OEM small body PWK and air striker) are NOT the same animal.

Maybe a different animal, but mine seems to react to different temp conditions pretty similarly

[Jeb]

One thing's for sure . . . I'll be somewhere in the neighborhood of a 2+ turns out!!

Why would you run at the "standard" (like 1 rev out) setting, anyway? Is there any disadvantage to the SSS? Having to spend a minute or two to adjust is small potatoes - especially w/ that finger-adjust screw - if that's the only drawback.

Riding in Oregon? In time, who knows . . . I'm a sucker for a road trip like that in the first place, bringing along the bike and riding when I get there certainly sweetens the pot.

I was actually in Vancouver/Portland area last week for 2 days (business). As we were flying in at roughly 11am there was a break in the clouds and I could see down along the Columbia River valley, somewhere in the general vicinity of Mt. Hood (I think). I was staring hard and I swear I could see some logging/fire roads (or something similar). 'Made it hard to concentrate on business things that afternoon. 'Have no idea if what I saw was actually territory one would ride in, but it was fun just to imagine!!

[canyncarvr]

Re: 'Why would you run at the "standard" (like 1 rev out) setting, anyway?'

Some have looked for it and not found it...likely due to the procedure used TO find it.

Enough HAVE found it (220 and 200 riders alike) that it's very unlikely to be an oddity with a certain group of bikes.

As far as the adjustment part goes, I adjust mine on the fly on a regular basis.

As you infer, once you know where it is and how well it works, anything else is simply a waste of time.


Mr. Wibbens: You're saying yours acts 'similarly'...how? As 'normal' or as in my concocted fairy tail (sic)?

bradf: As Jeb mentioned, there is more than one 'spot' on the farther out range of things that works. I've adjusted via 'normal' routine (in=richer =>colder) and found something that works better than what it was..but NOT as well as farther out. Try opposite of what you 'know'. May be a surprise lurking in those outer limits.



What's that smell?
.
.
.

Oh...it's just a road trip!

[Mr. Wibbens]

Fairy tale?

[Flying W]

So for giggles I raised the needle one slot (#4, CEK). Uggg, performance was markedly poorer. So I tweaked a few times and was close to going back to #3 when things got LIVELY at 2 & 5/16 out

Then I remembered the whole 3rd gear uphill 4-stroke thing, so I rode (actually, I zipped) out back into the woods and found me a good uphill. Except this time I let it ride at lower RPMs. The RPMs were low enough that it sounded like it was getting ready to shudder and die, and still it went.

So, I took the 220 out today to cut a couple trees that were down from winter storms. I had the head and carb done by Ron last month while replacing the piston. The bike is my wife's, but I will stop referring to it that way from this point forward (it is still hers, but the connotation is misleading). We have ridden it about 40 miles on 2-track, Coast Range of Oregon trails since the mods and all. It was noticeably peppier post-mods, but you'd expect that. BTW, the stock piston looked totally fine, but I can sleep well knowing that it won't be the reason the motor gets destroyed.

Back to the point, I cleared the 27" diameter tree that was suspended 30" or so above the trail with a true friend. It took two hours!

Back to the point, I tried the hillclimb with the AS out 7/8. Bike climbed it easily (It "way" out-climbs my 250F and that thing is a solid woods machine...except for being over-weight). I did it a few times, trying 3rd gear slow as I could and still make it over the imbedded rock face and tree roots. Then I twisted the AS out to 2.5 and tried it again the same way.

I did find (and Tony too), that the bike pulled better in the low range, but I did not have the experience Jeb described. I tried 2.75 with no change. I put it back to 2.5 and went riding (after all, that's why we were out there...the tree and the AS were just excuses).

Our family is heading out to ride tomorrow after church (mother wants to ride for Mother's Day ), so I'll try hunting around by 1/16ths if my DW let's me.

Maybe I should try the needle clip @ #4 first and put the AS at 2.

Any opinions?

[Jeb]

I tried the clip @ the #4 slot because of the cooler weather. I have had to adjust things a little since it's gotten warmer - I'm at a smidge past 2 turns now. It is interesting to note the direction I've turned the A/S to compensate . . .

I've gotten a little lazy in keeping up with the SSS - I need to spend more time experimenting (like trying that #3 needle again, just to see). It's so easy just to tweak it a little to find it - who knows, maybe there's a BETTER spot somewhere else!

My advice - keep looking, make SMALL changes. I don't think you'll hurt anything by dropping the clip a notch (#4) and it may expedite the search (that's a maybe, I've not had the mod long enough to really get a feel for it with 'sperimentation). Time permitting and test area permitting (maybe some other day, don't mess up Moms's day!!), do some "bracketing". I took a quarter turn section of the A/S (like 2&1/4-to-2&1/2), made very small changes and had a riding area with a straight section, a curvy section (to see accel coming out of curves), an easy incline and a pretty good hill. Keeping the "test area" small allowed me to repeat the course several times to get a good feel for the changes.

Good luck!!

[Colorado Mike]

Jeb,

I didn't get from your post if you have Ron's head mod or not. If not, do it. On a 220, you will have at least the same religious experience as his carb mod. For the 200, I hear the difference is less, but for my 220, I wouldn't be without it.

[Jeb]

Jeb,

I didn't get from your post if you have Ron's head mod or not. If not, do it. On a 220, you will have at least the same religious experience as his carb mod. For the 200, I hear the difference is less, but for my 220, I wouldn't be without it.

I got the whole sha'bang, my man!! Money very well spent, I am what you call a very satified customer.

There's no way of knowing what did what (carb mod vs. head mod) but I know I've got more motor from about every angle . . .

Anecdotal but interesting: my son and I went a ridin' yesterday afternoon at a local mx/trail park we frequent and ended up ridin' a little with a few folks that we've come to know. One of the youngsters is 15 and last fall he switched from a TTR125 to an RM250 (early '00s, and no, I didn't miss-type anything). It's probably obvious that he and his dad didn't realize how far he'd "graduated". How's he's managed to accomodate is quite impressive, really.

He was asking how similar my 220 might be to his RM so I offered to let him ride it. He rode sorta gingerly at the very first but rather quickly started juicing my KDX up pretty good. When he came around and stopped in front of me the first words out of his mouth were "SMOOOOOTTH" - he LOVED it! Several of us ended up making a trip down the "main" fireroad but he and I swapped bikes on the way out. I honestly think he would have rather just KEPT the 220 from the way he was talking about that trip. Along the fireroad are short hills climbs to the side and he started hitting them and was having a ball. I tried one good hillclimb but stayed on the fireroad after that, seriously, and he commented on how he generally didn't take too many of the hills on the RM . . .

Moral of the story: my 220 doesn't have the BOOM that that 250 had (which is fun for about 15 minutes) but it's got alot of the same gutsiness . . .

[canyncarvr]

RE: ' I tried 2.75 with no change. I put it back to 2.5 and went riding...'

Jeb said: 'My advice - keep looking, make SMALL changes.'

Yep.

I'm not sure how you missed that, but you did. The 'small change' aspect has been noted pretty much every time the SSS has been the subject of discussion. Making 1/4 turn changes most likely won't get you anywhere. You simply keep passing it with every adjustment.

'Small' means along the line of one indicator line thickness..that a reference to Ron's finger adjustable screw that has a red-inked index mark on its head.

Once you find it, you will know it. You will also know when, due to temp changes 'fer instance, it needs to be adjusted, and you will know HOW to do that. With Ron's knurled screw, you can easily do it on the fly.

It's fun!

[Flying W]

I'm not sure how you missed that, but you did.

I didn't miss it and I have the screw. I had worked 2 hours cutting out a 15' section of a 26" diameter D.Fir that was suspended about 40" above the hillclimb I wanted to use to set the screw. The guy I was with was very patient to burn up riding time for the tree cutting.

Once we got the rounds out of the way, we ran the bike up the hill a few times each with the AS set @ 7/8" (per Ron). Then turned it out to 2.5 (per Ron). We noticed an improvement (already stated). With that, my friend was ready to get some miles in. We'd all feel the same way if we were in his position. So I took a WAG and tried another .25 of a turn. Didn't notice anything so went back to 2.5 (thinking I might be leaning it out without any performance gain).

Today, I messed around a little on the street after washing the bike. I worked my way up to 2 7/8 where I could do 3rd gear starts from a dead stop by just rolling the throttle and releasing the clutch. Did it several times without ever being in danger of stalling. I may be "there"...but am willing to continue the tests on the dirt this weekend.

So, CC...mind PM-ing me where you reside and typically ride? Memorial Day weekend is coming and my wife may be willing to take a trip for some riding in the "mythical state of Jefferson".

[canyncarvr]

Sorry. My last post was snottier than usual. No call for that.

Bradf: '..For me it is about 1/32 turn for each 10 degrees..'

That's a perfect rendition...and example of how small a change makes a difference.

If we're lucky, the woods won't be closed by the end of the month. Fire season HAS been as early as the third week in May.

Sure thing! C'mon down! I've got accomodations for plenty (read: floor space for sleeping bags). You would be welcome!

Wibby and I have been riding Quartz Creek mostly. If you're coming down this way, though, you GOTTA ride on John's peak at least one day.
The peak for two days, quartz ck for one..that would get you a good taste of the airarea.

Give you a good case of monkey butt, too, most likely.

Even WITH ski's 'anti chafing cream' is sensitive spots!!

[curtisa]

I have a 2003 KDX 200 and I really like the bike . . I'm following these Post and I'm pretty sure AS stands for air screw? What does SSS stand for?

I've got an FMF gnarly and am in the middle of a fork conversion and will do the RB head and carb mods next. What about a V-Force Reed Valve? What's the best order to make these HP upgrades? THX!

[Indawoods]

It's the Second Sweet Spot.... it only comes with a RB'd carb.

FMF Desert pipe is the most common for the 200 ... however I run a woods pipe since I don't need any more top end. Just saying FMF Gnarly doesn't say much other than you are going to run a FMF pipe.

V-Force is the way to go.....

Suspension, Pipe, Reeds and RB'd at the same time.