Carb Slide

[tmc3c]

Has anyone ever taken off a .5mm off the air box side of the slide to make the throttle response better? Thanks Guys

Thomas Carmichael

[Lew Mayer]

Yes! Years ago I'm sure there was some update or service bulletin that had you file a notch in the slide to help clean up bottom end response. A friend of mine who was a Penton dealer remembers it too. I can't find it anywhere in print though. It came out at about the same time as the brass atomizer update, I beleive. I can't tell you the exact dimensions of the notch but I did it years ago and it helped out. Anybody else remember this?

Lew Mayer

[tmc3c]

Thanks Lew ! Can you remember if it was a notch or was the whole side cut back? Thanks

Thomas Carmichael

[john durrill]

I have seen just the notch Tom,
 I have an old 175 Jackpiner slide with the notch cut in it. Ask Speedy he will know. Its an old Bing trick that was used on Zundapps and Pentons years ago.
 I did a lot of trimming the slide cut away years ago on Mikuni's when we did reed kit intstalls on Hodakas. The differences in carb sizes, pipes and porting made it necessary. I had several 1.5 slides for the 26 mm body size and the 28 mm on hand  and would cut them for the specific bike. Saved me haveing to stock a bunch of different slides in different cutaways  giving us the right one for each engine to run its best.
John D.

[Lew Mayer]

It was only a square notch but I don't know the exact dimensions by the book.

Lew Mayer

[3putt]

Regarding the Bing carbs, does anybody know where there is a source for the cut away Atomizer/Vaporizer, Penton part #40-404 ?   I tried Bing several months ago when ordering some parts, but it didn't ring a bell with them.  I remember there was somebody trying maybe a year ago to locate them, and hoping they had success, and can pass it along to me please.  I'm making notes on the slide cut away, and hoping for the specs there as well.      Regards,   Nelson

wnm

[hrbay]

Just took a 30 mm Bing apart, and it has the slide notched, will measure it tonight and post dim.s.  
 3 putt, I have some old cut away spray bars, send me a pm, and I'll get one to you.

GC

[hrbay]

Hi Thomas, the dimension for the notch on the Bing 30mm is .192(w)X .081(h) as close as I can measure. I think it would be the same for most Bing slides.
  Nelson, I have two used extra's, one is brass and the other is (looks like) steel. A "Freebie" just let me know your preference and details in a pm. George


GC

[john durrill]

Thomas,
 I just talked to Speedy about the slide notch. Bing sent a service bullitin out on it. He will scan it and e-mail me with it. He said they cut it in all sizes of bings that didnt come with it. He said it is a 2mm x 2 mm notch dead center of the slide. It allows the slide to drop down much farther and the bike to idle cleaner.
 We will post the Bing fix as soon as we get it in the library.
John D.

[tmc3c]

Thanks Guys !!!       John you might have to help me to get into your site ! Every time I tried my password would not work and I couldn't get another one.

Thomas Carmichael

[john durrill]

Tom, sent you an e-mail.
 We have 2 files from Speedy on the slide notches. One is a factory fix from Bing dated 1974. Its in German and a little fuzzy but we will try and sharpen it up enough so we can post it.
The file with the small Bings shows a notch about 2mm x 2 mm
The one in German has several different cuts depending on which carb you have (the bigger 30 to 38 mm type 54's). The size notch apears to be related to which cutaway you have on your slide.
 When Peter gets home ill see if he can use Photo shop to sharpen up the words and #'s and we will see if Babble Fish can translate them enough  it will help you folks.
Sorry for the delay,
John D

[Lew Mayer]

Thanks,John, I'd love to print that out for my files.

Lew Mayer

[Larry Perkins]

On the 400's back in "The Day" there was a factory mod via bulletin that had the notch on the front and some cut-away on the back of the slide maintaining the original angle.  I just don't remember the how much part.  Too long ago and too many head wacks.

Larry P

[john durrill]

Thomas,
 From what we can translate and what George has found we think you can cut your 36 mm slide with a 4.5 mm wide 2mm high notch. We are hopeing Speedy can get us a copy that is not so fuzzy to translate. We can get most of the words but some of the leters and #'s are too fuzzy to make out.
 It looks like on the sheet, A is the slide cutaway measure in mm.
 L is the width of the notch for each slide and F the height of the notch is a constant not given. Some of the slides listed used a 7 mm wide notch but we are not sure at this time from the part #'s listed which one you have . If you use the 4.5 mm notch specs it should help and you can always go wider to 7 mm later if needed.
 Make sure you have a good slide , needle jet ( if in doubt change it out,:) they wear fast), needle, the float is the right height , float needle working like it should and  no air leaks.
 We posted both pages in the library. One thing we found that was very interesting. Bing sold chrome plated slides back then. I wish we had known that. A chrome slide would have lasted 4 or 5 times as long as the zink ones do.
 The Slides are listed by part #'s on the tech sheet. The 75 KTM parts book we have shows a 22-746 -1 slide for the 250 and 400 carbs (That would need the 4.5mm wide 2 mm high notch). The slides listed on the sheet are 22-745-..... last # depending on cutaway and size of the slide.
 Bet this is more info that we wanted to know chuckle chuckle.  Seems like the more I learn the more I realize how little I realy know
 Hope this helps folks,
John D.

[tmc3c]

Thank You John for going the extra mile for myself and others here in POG, you and people like you are what makes the POG group so great!! Now this notch is on the filter side in the middle of the slide,correct? Thanks Again:)

Thomas Carmichael