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Discussion starter · #41 ·
Well I finally got out for a quick cruise around the outskirts of town with a bunch of new parts on it. (5.5 rim, better tires, adjustable forks, better shock, carbon front fender, and a lot of Loctite and Antiseize.) Did 45-50 miles around on the backroads. She feels great...but...

The countershaft seal is shot from the chain being too tight before I got it. I could smell oil on the exhaust as I idled up the driveway.

From the looks of things on the parts fiche, the seal goes on from inside the cases. Which means pull the engine and split the cases.

I wish I still drank.

I'm going to bed sober and pissed off.

http://c8software.com.au/image/57/fiche/45/F8207C47D33DFF0FBD7A6C86B4599AFF.png
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The countershaft seal is installed from the outside, no problem changing it.

I have not seen a seal be damaged by a tight chain without a bad bearing behind it as the bearing is what keeps it centered in the seal. Double check the bearing and shaft and if you want to try seals are not that pricey or hard to change.
 
Discussion starter · #43 ·
The countershaft seal is installed from the outside, no problem changing it.
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Thank you, thank you, thank you...wonder why it shows it going in from the inside on the fiche?

I'll check the bearing while I change the seal, but it doesn't make any noise and it shifts like a dream. Maybe it just dried out sitting around and cracked now that I started riding it.

I always dreaded splitting vertical cases and messing up a perfect gearbox. The Jap stuff is pretty good about going back together and shifting O.K., but the european stuff always bothered me...
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Discussion starter · #44 ·
Well I finally got a chance to dive into the carbs today, since it fouled a plug on the way to church last night. Horz cyl wouldn't pull clean past 4k rpm.

My worst fears were confirmed when I got into the carbs, they were cleaner than the previous owner thought they were. But there were aftermarket needles in it. Real aggressive ones. The bike only has a K+N and a pair of slip-ons.

The pilot jets were jumped up from a 37.5 to 42.5s !! A 40 would have sufficed.

And the mixture screws were both over 4 full turns out. I'm surprised they hadn't fallen out.

I installed a pair of European needles set above the midpoint, blew out all the passageways and reinstalled the carbs.

I did a quick idle drop on each carb, and ended up with the mixture screws set about 1 full turn out. Very low since the pilot jets are so big. She runs real clean now, much smoother.

I'll order a pair of 40 pilots on my next big parts order, but installation will have to wait until this winter. I have other bikes to work on right now.

This is what the jet kit needles look like. Stock US needle on top, European needle in the middle, jet kit needle on bottom. Very aggressive taper.


 
Well your not far off from where I had to put mine to make it run clean--I had a 40 pilot jet and had to turn the fuel screws out 5 turns to get it right, so I went to a 42.5 pilot and now have the fuel screw out 1 & 1/2 turns and it now runs very nice, I do have the Factory Pro slide needles & their plated Emulsion tubes, & if I remember correctly I have a 135 main jet --The slide needle clip 2nd groove from the top
 
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Well I finally got a chance to dive into the carbs today, since it fouled a plug on the way to church last night. Horz cyl wouldn't pull clean past 4k rpm.

My worst fears were confirmed when I got into the carbs, they were cleaner than the previous owner thought they were. But there were aftermarket needles in it. Real aggressive ones. The bike only has a K+N and a pair of slip-ons.

The pilot jets were jumped up from a 37.5 to 42.5s !! A 40 would have sufficed.

And the mixture screws were both over 4 full turns out. I'm surprised they hadn't fallen out.

I installed a pair of European needles set above the midpoint, blew out all the passageways and reinstalled the carbs.

I did a quick idle drop on each carb, and ended up with the mixture screws set about 1 full turn out. Very low since the pilot jets are so big. She runs real clean now, much smoother.

I'll order a pair of 40 pilots on my next big parts order, but installation will have to wait until this winter. I have other bikes to work on right now.

This is what the jet kit needles look like. Stock US needle on top, European needle in the middle, jet kit needle on bottom. Very aggressive taper.


In European bikes the pilot jet for a 900 is 42,5. Bikes for the American market got a 37,5. So it might be possible that the 42,5 is stock for the bike (imported bike, imported carbs,...).

4 turns out for the mixture screw is not that uncommon. The screw will not fall out that easy. I think you'll find more bikes with the screw 4 turns out then with 1 turn out, which seems very little to me.

My bike (European 900SS) also has a stage 1 Dynojet, 42,5 pilot jet, K&N filter in stock airbox, Bos slip-ons and my mixture screws are 3,75 to 4 turn out.

Are you sure there are no internal leaks inside the carbs?
 
Discussion starter · #47 ·
In European bikes the pilot jet for a 900 is 42,5. Bikes for the American market got a 37,5. So it might be possible that the 42,5 is stock for the bike (imported bike, imported carbs,...).Nope, bike is a 900 SS CR, US bike only. Steel swingarm, cheap shock and forks, and a 4.5" rear rim. 42.5 is the only alternative jet on the 900 SS fiche. 40 jet has to be ordered off the 750 SS or Monster fiche.

4 turns out for the mixture screw is not that uncommon. The screw will not fall out that easy. I think you'll find more bikes with the screw 4 turns out then with 1 turn out, which seems very little to me. I was taught at school if you went beyond 3 turns out, you might need to go up to the next size jet.

My bike (European 900SS) also has a stage 1 Dynojet, 42,5 pilot jet, K&N filter in stock airbox, Bos slip-ons and my mixture screws are 3,75 to 4 turn out.

Are you sure there are no internal leaks inside the carbs? Yep, it runs cleaner now than it did. I let it idle too long in the driveway while I was getting dressed and that's why it greased the plug. Now it sits and idles without blowing black smoke out the pipes. Doesn't burble at 3000rpm on the road either.
Being a US bike, it came with 140 main jets. To make up for the smaller idle jets.

I do remember when we were selling these back in '95-'97, we didn't deliver the bike without putting the 40 idle jet in along with European needles...as long as we could get them. We also did a good idle drop on them before they left our shop. Then they ran like they were designed to.

When I was doing the idle drop yesterday, the idle speed was going down while I was coming out from 2.5 turns. When I went in with the mixture screw , the idle speed came up as I got near 1 turn...indicating the engine was happy. Closed the screw and it went down...come back out to around one turn and it was happy again. And the idle speed came up overall when I was done, had to turn it down about 100rpm.

I'm sure someone put this jet kit in over 20 years ago and just set everything by recommendations from a chart in the kit. And it ran like crap...and that's why it only had 12,200 miles on it.
 
As I have discussed with Rennsportmotorradd the bike knows what it likes and they each are different. I have to agree with BelgianDuc900SS that the "normal" fuel screw range is 3-4 turns out and outside of that usually throws up a red flag for me. Does not mean yours is "wrong" buy I believe it out of the normal range at 1 turn out. This makes sence to me in that the late model CR with marzzocci forks would most likely have 37.5 pilots so if the pilot is large I would expect the fuel screw to be closed more.

Keep in mind fuel screw settings are often different on different designs so where my kawasaki may want 1/2 turn out my Ducati wants 3.5 turns and the same engine with Keihin FCR's is again only 1/2 turn out. I think this is why Honda pushed the idle drop test back in the day it allows you to find the sweet spot and is still a good test today. Of course you can do the same test with a pilot size higher and lower and come up with different fuel screw settings so the question will always be larger pilot/less fuel screw or more fuel screw and smaller pilot. A CO meter would help answer the question.

In the end if you are happy with the way it runs there is likely no need to chase things, but keep in mind the last owner may have thought it ran well too.
 
In European bikes the pilot jet for a 900 is 42,5. Bikes for the American market got a 37,5. So it might be possible that the 42,5 is stock for the bike (imported bike, imported carbs,...).

4 turns out for the mixture screw is not that uncommon. The screw will not fall out that easy. I think you'll find more bikes with the screw 4 turns out then with 1 turn out, which seems very little to me.

My bike (European 900SS) also has a stage 1 Dynojet, 42,5 pilot jet, K&N filter in stock airbox, Bos slip-ons and my mixture screws are 3,75 to 4 turn out.

Are you sure there are no internal leaks inside the carbs?
Well this may well explain why my 91 900ss likes the 42.5 pilots-It was sold new in Italy not North America to a Ducati Tech Rep, he owned it until 2002 and I have no idea what if anything he may have done to this bike But my guess is he did something considering he had access to basically anything Ducati had considering his position with the company
 
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Discussion starter · #50 ·
As I have discussed with Rennsportmotorradd the bike knows what it likes and they each are different. I have to agree with BelgianDuc900SS that the "normal" fuel screw range is 3-4 turns out and outside of that usually throws up a red flag for me. Does not mean yours is "wrong" buy I believe it out of the normal range at 1 turn out. This makes sence to me in that the late model CR with marzzocci forks would most likely have 37.5 pilots so if the pilot is large I would expect the fuel screw to be closed more. True Dat !!

Keep in mind fuel screw settings are often different on different designs so where my kawasaki may want 1/2 turn out my Ducati wants 3.5 turns and the same engine with Keihin FCR's is again only 1/2 turn out. I think this is why Honda pushed the idle drop test back in the day it allows you to find the sweet spot and is still a good test today. Of course you can do the same test with a pilot size higher and lower and come up with different fuel screw settings so the question will always be larger pilot/less fuel screw or more fuel screw and smaller pilot. Yeah, Honda basic tech is where I picked up on the mixture screw settings during an idle drop. Running a little bigger pilot jet than needed will add extra fuel to the midrange transition due to the bleed holes behind the throttle flap. Makes up for having the thick stock needles. ;)

A CO meter would help answer the question. Wish I could afford one. :(

In the end if you are happy with the way it runs there is likely no need to chase things, but keep in mind the last owner may have thought it ran well too.I may be adding better driveabilty at the expense of ultimate HP, but sometimes "Stock is trick..".:D
I forgot to add yesterday, I mic'd the needles while I was messing around. The stock US needle and the Euro needle were identical from tip to top, and the top was exactly 3.00mm

The jet kit needle was 2.95mm below the clip grooves. Hmmm...an engineered leak? Or just bad quality control? Who knows. no markings on the needle.

I do know if I needed a jet kit , I'd probably buy a Factory Pro.
 
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