XSJohn's Kits- Hi Pef from 34's

jimdi · 650Rider Supporter Joined: Oct 27, 2005 Posts: 512

Ok as one who likes things "pretty factory" I must admit as one of xsjohn's guinnea pigs for his new hi-performance needles I was skeptical -

But when I put them in all I could say was "WOW"

I noticed a dramatic increase in performance from the the 2K-5K range - with a tremendous boost at highway speeds. When you are doing 40 and want to get to 65 - twist the grip and it felt like my old 68 chevy supersport with a quadrajet opening up the back barrels. (boy am I dating myself)

The best way to describe the extra "kick" was it felt like I lost 50 pounds.

I also noticed a drop in operating temperature due to the richer mixture on the high end - and I am still experimenting with optimizing that. Very Happy

It takes a little tweaking -and you can't be afraid to work inside your carbs - but if you're will to spend the time - it is worth the rewards.

Jim

Chopdoc · Full Member Joined: Aug 26, 2007 Posts: 47

I wanna know....what's up with the kits?

I am not at all intimidated by working on carbs.....

For some reason...don't ask me why....I want something "OEM-ish" on my XS as far as carbs.

That means I am looking for the best option as fat as OEM CV carbs of any year.

I run slash cut 1 1/2 inch drag pipes on an 81 XS with 4 inch baffles in them.

I may upgrade to pod filters...but I have the OEM air boxes at the moment.

I don't want to pay a bunch of cash for carbs when I truly believe that OEM units can do the job I need....if tuned properly.....

So what is the deal with these kits?

5twins · Full Member Joined: Aug 05, 2006 Posts: 1616

Yes they can. '76-'77 BS38s are the best in my opinion. They have the linkage and single throttle cable and are the least E.P.A. strangled.

Jim, I seem to recall that your carb problems a few months ago were with too rich running and blackening your plugs. Now you've added John's richer needles. Hows that working out for you as far as plug color goes?

Joseph · Full Member Joined: May 22, 2007 Posts: 767 Location: NY

I noticed the same with Jons nedles, actualy yesterday I was thinking the same thing as jim, when im crusing i used to hit the throtle glace back and forth at the speedo till i was going another 10-15mph faster now i hit it look away from it for a second i'm doing 75-80 before i know it, no breakup as there once was from 4000+rpm

xsjohn · Last edited by xsjohn on October 17, 2007, 6:05 pm; edited 1 time in total

Chopdoc.......I had a 77 and I agree it ran pretty good.........sold it to a friend of mine and we ride to the mountains guite a bit.........but there is no way the 77 can even begin to stay with my 80 now........I worked on these BS34's for 10 years trying everything ......the fed mandates blew their performance......I have spent the last 6 months testing these to make them as good as possible.........

y kit puts these things where they should be and even helps tame the hotter right cylinder........if you have a 81 I would suggest trying a set before you change carbs........the difference is amazing..........more torque....lots more power .....smoother.....and cruses the express like a dream..........I have put 10 extra thousand miles on my 80 testing these kits.....it has 49,000 now and has never run better........new rings last year...The stock BS34's just don't run right with out some help.....but their potential is amazing......

As far as Jim's left plug being darker.....it is still there and we can't as yet figure why.....Jim says it blackened even stock......I suspect the left carb on his could be pulling fuel from somewhere that it shouldn't....choke..?....my left doesn't do that......it's still a mystery and he is trying to figure it....

John

xs1961

Ive obviously missed the start of this thread...What needle kit you got John.?
what're they supposed to do?
Which carbs are they for stock 34's or 38's?
Got many or d'you get 'em in from some supplier?

xsjohn

It's one that I worked the slopes to do the job right.....I have plenty.....got tired of the crappy running stock setup......worked on this a long long long time....takes me about 2 hours to set them correctly..........

John

crumppa · Full Member Joined: Jan 17, 2007 Posts: 32

Just had a fantastic ride on my 83 w/ BS34s. I have a MAC 2 into 1 exhaust and Mike's pod filters. Been messing with the jets for a while and just never got it quite right. Always had a stumble at full throttle when going thru 4-6K rpm.

Saw this and other threads and PM'ed xsjohn. His needles, no kidding, really did the trick. Took some time to get then installed as I took the opportunity to completely disassemble and clean the carbs. Also, took some time to really dial in the sync and idle. All that really paid off. It runs like a champ and pulls strong., Thanks xsjohn.

FYI. Before the new needles, I had bumped the pilot jet up one tick to a 45, the air jet down to 127.5 and the mains up several notches to include 142.5, 147.5, and even a 152. Used shims on the stock needles. All these combos still had the stumble. With xsjohns needles I used stock mains and air jets. Ended up bumping the pilots up one tick to 45s. Plugs look fine.

jimdi · 650Rider Supporter Joined: Oct 27, 2005 Posts: 512

Yes - just to clarify - I have a Darker Left Plug (NOT BLACK!). An Yes this situation was there BEFORE I tried John's Kits. As a matter of fact... John's Kits actually helped the left plug improve (dark Grey)... and gave me more power to boot!

I am kind of a perfectionist - and the left plug is burning darker than the right - It's not fouling. It's running darker than the right - and I am on a quest to find out why...

Joseph is dead on with the decription - it's like turbo charging on the highway. The 3-5K range kicks now!

And 5twins - the needles and some tweaking helped the left plug - it's not serious enough to have to change plugs - it's not fouling - it's just running darker - and I like things even!

xsjohn · Last edited by xsjohn on October 15, 2007, 10:40 am; edited 5 times in total

Jimdi......I though it was fouling and black....My bad....would be a half a tad darker since it is a cooler running cylinder.....on mine I can see a tiny bit of difference......the right still runs a half a bit lighter on mine even though it is getting a tiny bit more fuel.........sounds like you are good to go.......nothing is perfect........since it was that way stock from day one you have a challenge on you hands making both plugs look exactly the same......

Another thing since it takes a bit longer for the left to heat up it may never have the same color.......maybe making it the same as the right woud be a step backwards.......????

John

jimdi · 650Rider Supporter Joined: Oct 27, 2005 Posts: 512

Actually - for the last month - I just trade the plugs between the cylinders every two weeks or so - without cleaning them - so that should give you an Idea of the difference - like I said - When I have time I will post a picture of the two plugs. We are getting cool here in Buffalo - riding days are getting short!

As far as compared to your plugs - I am about 1 shade of grey darker on the right and about 3 shades of grey darker on the left. Not quite carbon fouled - but definately darker than yours john.

royfisk

I dont know but one thing about 34"s Ive never seen a set that I was happy with the performance of. I cant see spending my time and energy messing with them when 38's really work well. 34mm vms however work extreamly well. Also noted the use of pods on bs carbs. Hows that working for ya, must change running charactoristics from day to day . Vaccume rise needles need a certain amount of vacume from both sides of the slide to work correcly and once you put on the pods that has changed. Vm's however dont require this and work rather well with pods. Your carbs are designed to work with the factory airbox. I have seen pods on the dyno tuned in and the following day it would be raining or barametric pressure changes and wolla the old girl isnt running right. THIS IS ACTUAL HORSEPOWER AND TORK MONITORING not guessing how it feels at 50-80. I would have to say that Johns kits probably do work But with these most anything would be an improvement but will never use them because why try to teach a useless dog new tricks when you can put on the tried and true 38;s and be done with it.

jimdi · 650Rider Supporter Joined: Oct 27, 2005 Posts: 512

Ok - first of all aren't 38's vacuum operated slides as well?
(sincere question)
2nd of all I am running standard air boxes - have yet to see the advantage of pods (I doubt they will make as much difference as the richer needles).

3rd - I enjoyed the learning factor while messing with these needles - if we weren't into messing with stuff - we wouldn't be on this website.

4th Needles are a lot cheaper than new manifolds - a new used set of 38's - pods - new jetting etc....

The needles offer a huge payoff for a small price ...

Now if you have a set of 38's and manifolds you want to send my way - I would be happy to give those a try too - and I promise my unbiased opinion on which I think really was better.

royfisk

Jimdi not trying to cause waves. I have been through hours and hours of messing with 34's and have never been satisfied with them. I was just voiceing my opinion. BUY all means if its doing what you want then its the way to go. crumpa brought up pods in his entry that is where pods com into play here. yes 38's are vacume and they where actually what I was watching on the dino. I would not spend the money to dino a set of 34 bs carbs. It would not be worth the cost of tuneing. I guess what I was trying to do was keep others whom are watching this forum in tune that there are better options then the 34mm carbs, not attack anyone.

jimdi · 650Rider Supporter Joined: Oct 27, 2005 Posts: 512

Not saying you were trying to - didn't think you were - I am interested in expanding my knowledge by tinkering.

Just saying on a practical side - if god give you lemons make lemonade.

I got a bike with 34's - needles are easier and cheaper than new carbs and manifolds / airboxes.

I sincerely would like to try 38's on my bike - but honestly I would have to get one heck of a deal on ebay to make the investment - just for curiosity.

No offense taken or meant...

Joseph · Full Member Joined: May 22, 2007 Posts: 767 Location: NY

What is vms.

xsjohn

Joe......vm's means very much spending.......round slides.....

Roy .....sounds like you had a real time of it with the BS34's.......

Nothing wrong with a good set of 38's.......my friend has my old 77 with them on it.........too bad for him though when we drag race....he gets to read my lisence plate if he squints.......

Seriously....the 34's are not as bad as their reputation........the 38's had no big brother messing them down.........

As usual maybe I started a good place to argue.....that's what makes this fun.......like marriage and all.......it takes more than 4 MM to keep a marriage together though.......

John

KYLEPRESTON

thought I should share my opinion. that is actually a picture of John when he was younger. All kiding aside john hooked me up with a set of his needles. I have 1980 tin tops. after having cleaned them I must have let sit a little to long in a humid area. I have gone throught and replaced with john's needle kit. runs like a top not to mention john's idea of the oil cooler.
Thanks again for all your help Kyle
P.S. I just posted pics of the ride in my gallery

xsjohn

Picture is not that long ago actually...5 years ago...it's amazing what you can do in Photoshop though........thanks for the kind word.......

John

5twins · Full Member Joined: Aug 05, 2006 Posts: 1616

Kyle, just checked out your photos - very nice job. One bone to pick, though. Your pods appear to be the tapered round style. Those are physically too small to flow enough air for these bikes ( just take a test ride with them removed, you'll see). You want the tapered oval style. And you want real K&Ns, not the cheap $12 knock-offs. John's needles may have helped but install the proper filters and it will run even better.

xsjohn

5twins....good point....if they inhibit the flow any less than the stock air boxes you may have some problems.........

John

KYLEPRESTON

thanks 5 twins I have cut out the rubber in key spots so it brethes better. I am looking for a set of stacks but I was worried it would be breathing to much! This is my first build and my first time modifying any bike I have been cautious with doing things.
Any suggestions on running stacks or some other item other than k&n I built that battery box and I can not fit the k&n's I am very tight it's a 73 frame it's shorter than the newer rides in the battery area.
I don't like the foam filters a lot of people run I am told you need to re-oil very often and all sorts of issues with them.
Cheers Kyle

5twins · Full Member Joined: Aug 05, 2006 Posts: 1616

Hmmm .... yes, then you may have clearance issues. The K&Ns, though, don't extend back much more (if at all) than your current filters, they extend down more.

xs1961 · Last edited by xs1961 on October 17, 2007, 12:12 pm; edited 2 times in total

These RAMAIR foam pods work best for mine...

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