Can anyone please provide BS38 slide specs ?

[gggGary]

I'm guessing you will still need to use caution in slide selection the early BS38 bodies had a much higher floor in the venturi area.
1971 carbs

1978-9 carbs

 

[peanut]

That appears to be a '77 or older slide. That type held the needle in the slide with only the return spring pushing down on the large plastic disc. It's a pretty simple set-up consisting of just 4 parts - needle, e-clip, retaining disc, and return spring .....



The '78-'79 slide was more complicated. It held the needle in with a snap ring on top of a sort of golf tee shaped plastic part. The needle itself had a couple spacers on it besides the e-clip and sat on a little spring .....

I missed this post 5T apologies.
I have only just noticed the 77 type needle plate disk lurking under the slide myself .

I have measured the slides that came with the 78-79 carbs and there seems to be a slight difference in the internal measurement between Garys and mine.
G's measures 45.32mm my slides measure 48mm from centre hole to top of slide internally.

I'm thinking now that I may have been lucky with this buy after all. If the builder bought and fitted a carb repair kit for a 76-77 BS38 the slides may be the original 78-79.

All I need now is someone to measure inside their slide which has a 502 jet needle and kit fitted . if it matches my slide at 48mm then all I'll need to buy will be the 502 needles, Z2 needle jets , O rings and fitting kit springs, washers, plastic spacers and plastic top hat piece.

 

[peanut]

I'm guessing you will still need to use caution in slide selection the early BS38 bodies had a much higher floor in the venturi area.
1971 carbs

1978-9 carbs

they are totally different carbs G ....

I have already established that the carbs I have are the late type 78-79 . They have the additional vents to the venturi mouths and the choke fuel and linkage arrangements are all a perfect match to my original 78-79 carbs.

All I need is someone to measure the inside of their slides from a slide that has a 502 jet needle fitted . Only the late VM22 carbs had this needle fitting type.

If I could get to my bike, I could remove my carbs and measure them but I'd have to empty my garage first and there is a van parked in front with a very flat tyre at the moment

 

[650Skull]

never mind all that crap skull lifes too short eh ?!
Me ?... I can barely remember what I ate for breakfast most days .

So what progress have you made on condensing this thread and working on your carbs .?

You asked........My memory is good, i fact i wish i didn't remember as much as i did.

Progress on the thread............as i said i removed my posts after you altered a previous post and argued about my ability to read threads properly. Altering your post was designed to make me look a fool and elevate yourself............

The progress my carbs...........After your behavior in that thread and towards me previously, i'm not interested in sharing my knowledge with you

 

[5twins]

Take a look at the big picture in Gary's post #18. Notice how the hole in the bottom of the slide for the needle is countersunk pretty deeply. That provides room for the additional spacer washers and little spring fitted to the 5O2 needle in this later slide. There is also a groove for the snap ring next to and slightly above his red arrow. Check to see if your slide has those features. The older style is virtually flat on the bottom of the inside, with just a small depression maybe a MM or 2 deep for the needle e-clip to fit into.

 

[peanut]

View attachment 116307
View attachment 116308
The measurement is from the top metal ring to the lowest point at the outside, the bottom is dished so it's lower in the middle

thank you G and 5T both.
Now I can see the recess pointed out by 5T I can see that the slides I have do not have this recess so they are definitely earlier BS36 slides dayam...
looks like these carbs are going to end up in my parts bin after all as i cannot afford or justify spending a further $200 on them to get them to spec.

 

[5twins]

You could jet them to match a needle that your older slide uses (4M1 or 4N8). Then it wouldn't cost that much.

 

[peanut]

You could jet them to match a needle that your older slide uses (4M1 or 4N8). Then it wouldn't cost that much.

yes I could but that would make everything twice as much work and confusing every time I came to clean and tune them every spring . I would need different needle jets and the complete needle fixing kits to go with them and I'd need a different range of pilot jets to my other carbs none of these components would be swapable between the 2x sets of carbs. I have spent best part of a week now searching the net for parts without success ...I can't even find anyone on the whole of xs650.com US or UK willing to sell me so much as a needle or needle clip so they are going in the parts box along with all the other valuable junk

thank you for all your help and advice its been invaluable ....we are very fortunate to have experienced owners like you willing to share their hard won experience with the rest of us