Affect of cutting slide?
- Thread starter Marklx
- Start date
desert_racer
LIFETIME SPONSOR
- Feb 2, 2000
- 538
- 0
Thanks acutemp. That clears it up completely. I'm glad I saw that cause I thought... well.. I don't know what I was thinkin...:confused:
'SLIDESHOW'
This is the first time I posted a pic on the web, so you'll have to bite the bullet, copy& paste til I get a better way figured out. Really hope it works!!!
Please try it. Ok, I found a better way, just click on the link :o
http://photos.yahoo.com/bc/chiefcam...hbw2HA&.dir=/My+Photos&.dnm=slide.jpg&.src=ph
I think the comparison pics are great. Also Spanky does a nice job of explaining it. RM_GUY, sorry I didn't get to ya sooner. I did manage to get a decent picture after a little experimenting. (and a lot of sleep) :)
I filled in the area of the slide that was ground, in red. That is the only place to grind. Although the red area looks flat from the angle of the shot, It slopes a little steeper than the rest of the 'bowl'.The grinding came close to the bottom of the 'U' shaped notch, just barely touched it if at all. It does taper off to nothing as it approaches the corners.
Correct me if I didn't understand, but I believe the lowest part of the 'bowl' would be 1mm lower than stock, being cut 1mm. (That's w/ the slide standing upside down of course). I'm going back to sleep.
Joe Chief
This is the first time I posted a pic on the web, so you'll have to bite the bullet, copy& paste til I get a better way figured out. Really hope it works!!!
Please try it. Ok, I found a better way, just click on the link :o
http://photos.yahoo.com/bc/chiefcam...hbw2HA&.dir=/My+Photos&.dnm=slide.jpg&.src=ph
I think the comparison pics are great. Also Spanky does a nice job of explaining it. RM_GUY, sorry I didn't get to ya sooner. I did manage to get a decent picture after a little experimenting. (and a lot of sleep) :)
I filled in the area of the slide that was ground, in red. That is the only place to grind. Although the red area looks flat from the angle of the shot, It slopes a little steeper than the rest of the 'bowl'.The grinding came close to the bottom of the 'U' shaped notch, just barely touched it if at all. It does taper off to nothing as it approaches the corners.
Correct me if I didn't understand, but I believe the lowest part of the 'bowl' would be 1mm lower than stock, being cut 1mm. (That's w/ the slide standing upside down of course). I'm going back to sleep.
Joe Chief
Last edited:
I don't know if this will help or just add to the confusion. In the link below, the photo on the left was my stock slide (#5). The one on the right is after it was ground to a #7 (I did not do the work myself).
http://ourworld.compuserve.com/homepages/rushbe/rb3.jpg
http://ourworld.compuserve.com/homepages/rushbe/rb3.jpg
dirt bike dave
Sponsoring Member
- May 3, 2000
- 5,349
- 3
whyz - removing any material from the bottom of the slide would make it run leaner. It's all about finding the optimum throttle response. On some bikes, maybe only 0.5mm would be enough. Yeah, if you cut too far, you might have to buy a new slide - better to go a little bit at a time if you're unsure.
The slide cutaway only effects the amout of air entering into the engine at low rpm. Most seizures are from too little fuel at high rpm, which is controlled by the main jet and not effected by the slide.
The slide cutaway only effects the amout of air entering into the engine at low rpm. Most seizures are from too little fuel at high rpm, which is controlled by the main jet and not effected by the slide.
I just cut my slide yesterday with a rat tail file and polished it with 150 grit
wet/dry sandpaper and crocus cloth (really fine 600+ sandpaper) It looks good
and I'm excited to try it out. It only took about 10 minutes for the whole
thing. Pretty easy.
wet/dry sandpaper and crocus cloth (really fine 600+ sandpaper) It looks good
and I'm excited to try it out. It only took about 10 minutes for the whole
thing. Pretty easy.
It's just a round file that tapers down and they come in all sizes. The one I used was about 3/8" diameter at the widest point.
Before you do anything make sure you re-read all of the post so you understand what you're getting into. Not to scare you but it IS possible to ruin your slide if your not careful. Make sure you don't make the cut out any wider and don't touch the very bottom of the slide.
Good luck
- Thread starter
- #36
Chief, Brush, acutemp,
The pics are great, I've got my slide marked and ready to go. Only thing, I've got new leaner needles that I now find out are backordered 'til next week. I want to try that approach first before I grind. I know the cutaway helps on the '01, but haven't heard as much griping about the '02, so thinking maybe the $15 needle will do the trick. If not, the slide is out again. Funny thing about the pics. On my desktop high zoot 19" monitor, it was hard to see the differences, but on my 3 year old laptop, they are clear as can be. Guess the lcd has better shading. Whatever the case, thanks for all the great input! Lots of people will be busy this weekend 'cuz of those pics.
Mark
The pics are great, I've got my slide marked and ready to go. Only thing, I've got new leaner needles that I now find out are backordered 'til next week. I want to try that approach first before I grind. I know the cutaway helps on the '01, but haven't heard as much griping about the '02, so thinking maybe the $15 needle will do the trick. If not, the slide is out again. Funny thing about the pics. On my desktop high zoot 19" monitor, it was hard to see the differences, but on my 3 year old laptop, they are clear as can be. Guess the lcd has better shading. Whatever the case, thanks for all the great input! Lots of people will be busy this weekend 'cuz of those pics.
Mark
To all concerned:
I did the mod this weekend. I spoke with Eric on Saturday at a seminar at NEC (North End Cycle). He explained where the slide should be cut and where not to cut. I used my dremel tool to remove the majority of the aluminum and then 400 and 600 grit sandpaper to polish. My slide now looks like the one pictured(left) in the thread above. The cut is only done to the radius(round) portion of the slide, not the straight taper at the bottom or the front of the slide. The small notch at the bottom of the front is the idle circuit, DO NOT modify.
I did the mod this weekend. I spoke with Eric on Saturday at a seminar at NEC (North End Cycle). He explained where the slide should be cut and where not to cut. I used my dremel tool to remove the majority of the aluminum and then 400 and 600 grit sandpaper to polish. My slide now looks like the one pictured(left) in the thread above. The cut is only done to the radius(round) portion of the slide, not the straight taper at the bottom or the front of the slide. The small notch at the bottom of the front is the idle circuit, DO NOT modify.
How does it run!! I have no idea the top end is still off and am waiting for the rings and top end gaskets. With any luck it wil lbe together by this weekend. But we are also supposed to get snow this week. So I may not have the opportunity to try. Knowing that the bike runs rich already and talking with Eric gave me enough incentive to try modifying the slide. Hey, if I modified to much I know where to get a new one:scream: .
- Thread starter
- #40
Finally got my 1/2 clip richer needle (running on 2nd clip, was 3rd on stock needle, so 1/2 clip leaner now) and gave it a test run over the weekend. WAY cleaner down low, clears out faster. But still have that little cackle down off the very bottom before it hits the powerband.
Haven't done the slide, as wanted to see what happened with the $12 needle. I'm happier, but what's the opinion of those who've hacked at the slide. Is it that cackle at initial roll on that will be helped, or am I dreaming? With all the great input here, it is almost too easy to do this, but don't want to blow a slide if I'm barking up the wrong tree.
Mark
Haven't done the slide, as wanted to see what happened with the $12 needle. I'm happier, but what's the opinion of those who've hacked at the slide. Is it that cackle at initial roll on that will be helped, or am I dreaming? With all the great input here, it is almost too easy to do this, but don't want to blow a slide if I'm barking up the wrong tree.
Mark
SLIDES THE WAY TA GO!
I HAVE JUST FINISHED ALL THE ARTICLES ON THIS THREAD AND
I'M GLAD I READ IT. I'VE GONE THRU NEXT LEANER NEEDLE AND PILOT.
THEY SEEMED TO WORK "AROUND THE PROBLEM."
I' DEFINATELY GONNA DO SOME CUTTING NOW.
AWSOME THREAD.GOOD JOB ON THE PICS.EXPLANATIONS ALSO.
I HAVE JUST FINISHED ALL THE ARTICLES ON THIS THREAD AND
I'M GLAD I READ IT. I'VE GONE THRU NEXT LEANER NEEDLE AND PILOT.
THEY SEEMED TO WORK "AROUND THE PROBLEM."
I' DEFINATELY GONNA DO SOME CUTTING NOW.
AWSOME THREAD.GOOD JOB ON THE PICS.EXPLANATIONS ALSO.
CR Swade
~SPONSOR~
- Jan 18, 2001
- 1,764
- 5
I'll tell you guys, I was nervous about it for a couple of months. But after doing every thing except the slide cut and not getting the result I wanted, I started cutting. I cut 1mm and noticed immediate throttle response on the stand. I rode it and had better transition from basement rpms to mid. But it was still a little vague, so I cut .5mm more off. Instant success! The bike had much crisper low and now the air screw and clip adjustments were all that was needed for temp/humidity changes. Before the slide mod those adjustments didn't have as big of effect as they normally should.
Look at it this way, 1mm cut on a poorly jetted bike (rich down low) that nothing else will fix is not a big gamble. In my CR's case, I couldn't really screw it up any worse than it came from the factory. It works well.
Look at it this way, 1mm cut on a poorly jetted bike (rich down low) that nothing else will fix is not a big gamble. In my CR's case, I couldn't really screw it up any worse than it came from the factory. It works well.
Although Eric made the first cut on mine, I may take more off this summer. The effect was dramatic, but the bike ran perfect, PERFECT, at 40 degrees. Just have to see what it's like at 80 degrees. If the jetting doesn't help, I won't hesitate to cut gradually, say .5mm at a time. I'll also be prepared to take a hit if it doesn't work out. I'm pretty confident since Mine is already cut, so I know where to go with it, but also now know what the bike is capable of. SSSMMMMMMOOOOOOTTTTTHHHHHHH. Nothing like it was off the showroom floor. I had much the same experience, the bike didn't respond well to jetting changes until this was done.
Joe Chief
Joe Chief
I still might give the slide cut a try, but I have been quite happy with the Yamaha needle jet mod...maybe it's not perfect but it's close, and much easier to just swap jets than to worry about machining. I agree that swapping needles is just working around the problem...the NEEDLE JET is a better mod. Of course, a leaner pilot is also a must...mine is a 25, and if anything is a bit lean but workable.
I finally got my bike back together enough to start it and break the new piston in. The affect of cutting the slide is really noticeable. It is snappier off the bottom (note to self: Buy grass seed :scream:) and seems smoother. It was 45 degrees out and I had to turn the air screw in to ¾ out to get rid of the baaawaaah sensation but then it ran good.
Now my question is what about the choke adjustment. The manual says it affects carburation up to 3/8 throttle. It looks like I’ve got 5 things to adjust for this throttle position (air screw, pilot jet, slide cutaway & choke setting and the needle to a small extent). I’d like to understand which one has the greatest affect on throttle response. The slide cutting made a big difference but I’d like to fine tune it more.
Has anyone experimented with the choke setting? I would think that you could compensate for a lean/rich pilot jet by adjusting the choke. Mine is at the stock setting (2 turns/12 clicks).
Now my question is what about the choke adjustment. The manual says it affects carburation up to 3/8 throttle. It looks like I’ve got 5 things to adjust for this throttle position (air screw, pilot jet, slide cutaway & choke setting and the needle to a small extent). I’d like to understand which one has the greatest affect on throttle response. The slide cutting made a big difference but I’d like to fine tune it more.
Has anyone experimented with the choke setting? I would think that you could compensate for a lean/rich pilot jet by adjusting the choke. Mine is at the stock setting (2 turns/12 clicks).
- Thread starter
- #47
I tried going leaner on the choke, out to 16 or 17 turns, and found a little detonation their (50/50 100 octane/91) when I'd shut off and quickly get back on it. Didn't help clean up the bottom end either, so not too successful. Haven't done the slide yet, as just now playing with the 1/2 clip leaner needle and air screw settings. While I still have a little crackle on the bottom, running on the 2nd clip from top has significantly cleaned up acceleration. Much less effort to get out of turns quickly, and less clutch slipping. Next I'm going to try the one leaner needle, then cut the slide.
mg
mg
I ground my cut away several times with some success but I got frustrated because it was not leaning up as fast as it did with round slide carbs.. Then I got another idea. I relieved the "c" shaped post that rises from the bottom where the needle enters it's holder. I found this much easier to so. You see when the cutaway is relieved it doesn't let more air in, it lets the same amount of air thru a larger area,therefore; slowing down the air speed which is responcible for the low pressure area that "sucks" the fuel up. Lower air speed equals less fuel not less air. If anyone is interested in this technique I can explain it in more detail.
Your ridin' bud Kurt
Your ridin' bud Kurt
Choke Adj
RM_GUY,
I experimented w/ the choke quite a bit. Mine was running best at only 4 clicks out( the last time it was together :) ) I was mainly dealing with the detonation problem. The response was good.
As far as the yard, I've allowed myself a few designated 'Roost Areas'; One or 2 sharp turns, Sand pit where the soft pool goes during summer. I really enjoy seeing the 'Bike Sign' whenever I'm out there mosying around.
I think it's great that you got that good of a result from a simple mod!!!
Joe Chief
RM_GUY,
I experimented w/ the choke quite a bit. Mine was running best at only 4 clicks out( the last time it was together :) ) I was mainly dealing with the detonation problem. The response was good.
As far as the yard, I've allowed myself a few designated 'Roost Areas'; One or 2 sharp turns, Sand pit where the soft pool goes during summer. I really enjoy seeing the 'Bike Sign' whenever I'm out there mosying around.
I think it's great that you got that good of a result from a simple mod!!!
Joe Chief
