About a month ago I left the house on my red ‘76 Standard (the infamous Lucille) and she started fine and idled OK - but as soon as I pulled out of the driveway, she was missing and stumbling and I knew something was wrong. I had just installed a PAMCO w. E-advancer and it had been performing great with instant starts and a steady idle. I had put around 250-300 miles on her with the PAMCO and all seemed well. I turned back and parked Lucille and took Sylvia (2007 ST1300) instead.
Hmmmm....what the heck was wrong with her...ignition? ...carbs? Dang it - I wanted to ride! Well, life has intervened over that month and today was the first time I had a chance to dig into it. I checked over all the PAMCO wiring and everything looked so I assumed that it was more likely the carbs.
When I resurrected the bike in the winter of 2016, I cleaned the carbs with solvent and compressed air and made sure that all of the passages were free of crud (and there had been a lot in there). The first start went fairly well and after that, she started pretty easily and ran better and better to the point where I have put nearly 4000 miles on her (some it at pretty high speeds actually). She was always easy to start, idled OK and every time I looked at the plugs, they were a pleasing brownish colour. In my haste to get her going, I neglected several key details including checking that the correct jets were installed and cleaning the enrichener plungers. I also will ashamedly admit that I have not yet synchronized the carbs - she ran so well, it simply didn’t seem necessary.
I also failed to install fuel filters (cue horror movie music here).
Anyhow, this morning, following the excellent and comprehensive XS650 Carb Guide (thanks guys - sure wish I had had this last time!) I pulled the carbs and got right into them. Here is what I found:
- the jets are correct for the year (122.5) and the left one was crudded up a bit;
- both jets had
buggered-up slots indicating that someone has been in there before and they were naughty with bad screwdrivers (I have found that just about every part of Lucille has been “previously enjoyed”);
- the pilot jets also look to be correct and one was clogged;
- there was crud in both float bowls (surprise!);
- the left hand needle holder would not come out of the bore of the carb slide. This seemed odd. The little plastic disc got stuck about halfway up and no matter what I tried, it wouldn’t come out. So, I just wiped off the needle, made sure that the second hole in the slide was clear and put the assembly back in;
- I tested the slides and diaphragms as per the Guide and all is well with them;
- the float heights were way off - likely around 27 mm or maybe even a bit more - versus the required 24 mm;
- the enrichener plungers were both cruddy - so I have replaced them with new ones plus I greased the spots where the rotating choke linkage passes through the carb bodies.
My other key goal was to install fuel filters on this raunchy old gal and so I had bought those conical things and thought I had come up with the worlds cleverest idea to fit them into,the incredibly crowed mid-body area of my XS650. Let me say that there is a LOT of stuff between the rear side of the cylinders and the frame just ahead of the battery box. You’ve got to fit in the carbs, throttle and clutch cables plus some electrical wiring - plus the bulky airbox assembly. Finally, the petcocks are nearly on top of the carbs with very little real estate for filters plus, it isn’t easy to sort it out so that the hoses don’t have a loop in them (which would impair reliable fuel flow).
The problem is that the filters are actually fairly long so getting the hoses routed isn’t easy. Here is what I came up with (pretty damned smart eh?). I’ve got the LH carb feeding off the RH petcocks and the LH carb....etc.
View attachment 107061
Well.....it does damn work, I’m afraid. The filters are simply too big to go between the frame tube and the carbs - no way / no how.
At that point, I ran out of steam - any thoughts on putting fuel filters on one of the things - would be most welcome.
Pete
