Another acquisition - XJ900F 1992

[Grimly]

The XJ900F has been busting my chops the past week, with a pair of iffy coils - I fitted a set of CBR1000 coils which worked great, but one of them started to fail the next day. Bummer.
So, back to the original set and temp repair them - one was a Chinese no-name cheapy, with HT leads made of a particularly stringy cheese, and the other (OEM) coil had a rotten LT feed. Both repaired and put back on, but the OEM coil has drifted high in secondary DC resistance. It's time to treat the bike to a brand new pair.
Anyway, happiness of engine re-established and it becomes obvious after a v.careful tune up the muffler packing in the (ex-H-D Dyna mufflers) left hand side has shifted. Looking up H-D forums, it seems this is quite common, so tomorrow I'll gut the mufflers and re-pack with stainless pot scrubbers.
That'll show 'em.

[Grimly]

The repacking of the mufflers hit a cliff - the LH one came apart easily enough, but the packing on the RH one had stuck firmly to the outer shell and the absorption pipe, so just bunched up and wouldn't allow the pipe to come free. My efforts to free it resulted in the baffle plug being set free to find itself. With no chance of welding it back in, I decided to even them up by removing the LH baffle plug.
Hmm...
Initially it seemed ok and the bike was running well, but as time went on there appeared a horrible off-beat note, steadily getting louder and harsher.
After a day of being assaulted by this nasty off-beat sound, which made a noise like a defective Ducati (I'm sure this is caused by the connector pipe underneath, and the problem of 1&2 and 3&4 feeding into LH and RH mufflers respectively) I had another go at them. I effectively put the baffle plates back in place and augmented them by holding a stainless steel pot scrubber in the main absorption pipe, via some washers and threaded rod.
Hola! Sanity is restored. It now revs cleanly and quietly.
I'm looking at the old Jama aftermarket mufflers that came off and wondering if I can simply re-shell them - those worked very well and were essentially a direct copy of the factory pipes.

[Grimly]

To say I am chuffed is an understatement.
Foul weather the past few days precluded any activity with the XJ9, but today was clear and dry.
It's running quieter than it was when I bought it with the Jama mufflers on - and those were pretty quiet. I'd say it's now as quiet as the standard factory pipes.
It's pulling excellently in all gears, too; no flat spots or hesitation - in fact, the scenery goes backwards at quite a satisfying rate in any gear
Only downside is now I can hear all the chirps, whines, clinks, burbles and gasps of of the rather old engine.
Runs like a sewing machine though. Admittedly, a sewing machine that's done a shedload of work, but still.
I quite like it this way - I was getting tired of the racket. Think I'll get another few of these Hardly mufflers now that I know what to do with them.

[Grimly]

Finally got around to tackling an annoying oil filter leak on the pre-Divvy XJ900.
Turned out to be the large O-ring at the back of the cooler take-off block, which had never been off since it left the factory. As a result, the O-ring was rock-hard and weeping. Took the opportunity to suss out why the XJ600S bits I bought to convert it to a spin-on filter wouldn't fit nicely, and it turned out just need a slight bit of butchery with a slicer, reducing the big internal hollow bolt head by about 3mm, to allow the converter plate to sit on it.
All finished and holding oil nicely...

filter fitted 01.jpg

[dorkburger]

I envy those with spin on filters....

[Grimly]

I envy those with spin on filters....

So did I. I've looked at possible ways of converting the GS to such, but it's too much of a hassle.
At least, for now.

[Grimly]

More Single Carb Adventure coming up..

A recent descent into bad running had me examining the carbs, and by the time I buy new rubbers (hard and broken/leaky) front and rear and new diaphragms, plus the basic cost of a minor carb refresh kit for the float chambers, it all adds up to more than I feel like paying.
A Weber is the weapon of choice, this time.
I had a close look at the room available and Yamaha having moved the alternator and starter inboard and upwards means there's no real room for an SU in there unless I have it poking out the right hand side, meaning there's going to be a torturous passage for fuel/air mix, so rough measuring up revealed just about enough room for a simple branch manifold with a downdraught Weber sitting directly on top and it can poke up between the two frame rails. Hopefully there will be enough space above it to allow a smooth flattened elbow to get air into the top of it and a cool air hose can be run to the front of the bike, with a filter cone on the intake end (details to be finalised).
I've scored a Weber 32 DIR, which is a close relative of the DGV and even though it's a production-line carb originally fitted to small Volvos, the jetting in it is changeable enough to allow proper running on a 900. I'm fairly sure it will be an improvement on the SU, as the first choke is 23mm, the second choke is 24 mm, and there are a couple of extra enrichment circuits that might (or might not) help out.
To start with, the manifold will be roughed out using 1.5" mild steel thin-wall tube going into each port stub (I'll use the original port stubs for fitting, then replace them with a set of the cheapies from China), The feed tubes will be welded onto a short section of 2" square box , mounted longitudinally, centred on the rear of the head. Cylinders 1 and 4 will be fed via slightly longer curved elbows and cyls 2 and 3 via shorter elbows.
This is to attempt in some way to give each cylinder a chance of getting an even feed, both from the primary choke and the secondary choke in turn.
It won't be be perfect, but it will work.
I expect I will drop some power, but the mere fact of having a decent choke area I might not lose too much - I foresee a loss of at least 10hp and likely 15.
However, it it gets to 115 and can sit there without being too rich or too lean, I'll be happy enough.

[850 Combat]

I bought two 650 Secas brand new in the late 80s. I bought another one in the mid 90s with a bunch of small problems for a couple hundred. My brother still has one of them. The Hitachi carbs were more prone to clogging with old fuel than I was used to. Compared to a GS850, it handled a bit better, but was less comfortable. I assembled a complete NOS 8" headlight assembly over a period of years and a saved search on E Bay. I sold the bike in about 2014 though. Made money, which for me never happens. I still have the headlight and an oil cooler from a Canadian bike I planned to install but never did. Those and the CBX are the first bikes I can think of which used a jackshaft to make the crank case narrower.

[Grimly]

Yes, there's a difference in handling, and not in a good way.
Even though the suspension and brakes are a generation newer, Yamaha spoiled it by the engine feeling as if it's too high in the frame. It isn't, of course, but by shifting the mass of the starter and alternator upwards they adversely affected the overall feeling, especially when I step off the GS and onto the XJ.
The XJ always feels like it wants to tip into the corners a bit too readily, although this can be influenced by tyre choice too.
It's not a bad handler, just different.