[Witworth]

Based on some of your previous posts.......This is coming from the suspension guru who claims that plastic CBX swing arm bushings never wear out. Some poor slob would wobble into your "shop" on a CBX and then based on your infinite wisdom, you would sell him a fork brace and send him on his way.

The 1st model CBX swingarm bush problem is largely urban myth. I've never had any complaints from riders of bikes that I've improved : absolutely exactly never. The comments usually are: ' The bike handles far better than when it was brand new '.

I sell riders the whole package, not just a simple bolt - on. They leave with their wallet much lighter, my wallet crammed with notes and they have a bike that only gives them pure joy to ride fast.

Danger, is my business.

 

[hillsy]

I sell riders the whole package, not just a simple bolt - on. They leave with their wallet much lighter, my wallet crammed with notes and they have a bike that only gives them pure joy to ride fast.

You never fail to disappoint when it comes to speaking crap. I'll give you that.

On the other hand you always fail when it comes to offering any evidence to prove anything you claim to be.

I'm beginning to doubt if you can even make coffee now.

 

[Sabre Cafe]

...and now, back to 8ball's winter project, maybe.

 

[8ball]

I forgot what this thread was about........

 

[Sabre Cafe]

I forgot what this thread was about........

Seems like they all end up being about Witworth...

 

[Sabre Cafe]

I forgot what this thread was about........

Seems like they all end up being about Witworth...

I like your double seal solution. Don't see why it shouldn't work just fine.

 

[8ball]

The basic function of the bike has been tested, and I think it is going in the right direction. I still have some tweaks to go....ie. cartridge emulators and figure out a better headlight solution. (It's fine during the day, for visibility, but the light beam is not so good at night for seeing the road)


My first priority was to update the electrical system. It is, after all 35 years old, and a Suzuki to boot. That's two strikes against, for anyone counting.


I Ditched the points for a DynaS:

Upgraded the Coils:

Added a relay to supply the coils and DynaS ignition directly from the battery, instead of through the ignition switch. The relay is activated through the ignition switch, but the main contacts are wired up to a fuse directly from the battery, and feed the coils:

Replaced the old shunt type reg/rec with a modern Series SCR type from a Polaris, and spliced in a harness from a Triumph Bonne:

I did a static timing adjustment and was perplexed that I had to have the plate almost completely retarded to get it timed. Once I got it started and did a dynamic timing check it did need a little advancement, but not much! I still find it odd that the adjustment is so far to one extreme. I don't like any adjustments that are set at one end or the other. Maybe they figure that the user may want a bit more advance for performance, and they give you room to do that. It is unlikely that anyone would retard the timing from the factory setting. I dunno. That's my theory....and I'm stickin' to it! Regardless, it fires up and the timing is spot on,and the charging is strong with this one, Obi Wan.

Now I need another warm dry spell to road test, but Mr. Weatherman isn't cooperating!

 

[8ball]

So...I ordered a new ignition cover gasket. It was cheap, but took 4 days to arrive. I took it out of the package and put it on my end table beside my sofa. I got up for just a few seconds, and when I returned, I found the dog looking at me with a "what?" expression. There is a reason we've nicknamed her "The Shredder"!

 

[8ball]

Since I broke my knee this winter, my riding season has not gotten off to a ....well, non-existent start. So instead of riding the GS to evaluate the front forks from the 82 GS and making changes in increments, I decided to go ahead and install emulators and the stiffer springs that were installed in the original forks, along with pre-load spacers to eliminate the air assist that the 82 forks had.

Then I went to put it together, and found on of the forks has a slight bend! AARRRRGH! I had checked them before, and hadn't noticed any bends, but this time when I put them on, the fork lowers were about 1/4" too close together to put the wheel back on. I loosened the pinch bolts on the tri[le clamps, one side at a time, and spun the forks in the clamps. Left side was straight, but sure enough, the right fork has a slight bend. CRAP!!!

I have a suspension guy locally that has the v-block and press set up to straighten it, but he is heading to Road Atlanta for the MotoAmerica races this weekend, since he is the K-Tech rep. He won't be back until next Wednesday, so I guess it'll have to wait. But since I have to disassemble the fork again, it'll give me the chance to take the pictures that I failed to do during the emulator install.........

 

[8ball]

I made a few adjustments. I've had some rough running cruising at less than 1/8 throttle (just off fully closed). The idle circuit looked rich....black sooty plugs when doing plug chops after running (intentionally) in the "sputter zone" for a couple miles. I had gone up one size on the #1 pilot jets (from 15 to 17), so I put the originals back in, synched the carbs and adjusted my pilot air and fuel screws. Now the plugs look much better at idle and after the "sputter zone" test....yes, still had a sputter. #1 cylinder was still running rich......another tweak of the air pilot screw and it seems better, now. I will need to take it for a test ride today, or tomorrow. I still need to remove the front end and take it down to Cycle Tech to straighten out the fork leg......

Synched up OK......before, 1 and 2 were at 40, while 3 and 4 were at 20

 

[8ball]

The last carb adjustment seemed to solve my off throttle issues, on to that pesky bent fork leg. Front end removed....

Right leg disassembled:

As far as the emulator installation, these two 5/16" holes had to be drilled into the damping rod, and the existing hole enlarged to the same size:

Set up on my press, so I could see how bent the for was:

I took the fork leg to the local suspension guru, Jon Tyus at Cycle Tech Racing to straighten it out.

Reassembled the fork, and set the fluid to 140mm (15wt oil):

The slide on the scale is set to 150mm, - the 10mm showing on the bottom = 140mm

I also reduced the pre-load spacer from 20mm to 10mm because the front felt a little harsh. This brought my static sag from 23mm to 37mm.

All back together, again:

 

[8ball]

Out playing, today. Carburation is much better, and the suspension is pretty close. I couldn't really throw it into the turns because of my knee, but it doesn't seem to want to do anything weird.

Out playing, today. Carburation is much better, and the suspension is pretty close. I couldn't really throw it into the turns because of my knee. I can't get my left foot back enough to keep the ball of my foot on the peg, and I don't have the strength to hang off in the lefts. But I could push it enough to tell it doesn't seem to want to do anything weird, and the front and rear are working together, like they should.

 

[ProTouring442]

Just watched you video, Sweet!

Where in East TN? I'm in between Farragut and Lenoir City, south of Knoxville.

 

[8ball]

Maryville, so less than 30 miles from you.

 

[8ball]

I don't like how far the throttle rotates from closed to WOT, so I played around making a quick turn throttle.

The blue tape on the housing marks the range of the stock set up:

I cut a piece of 1" PVC Sch 40 pipe:

Sliced a little out and wrapped it around the throttle cam:

...and here's the difference in the range from closed to WOT:

It works fine with the return cable disconnected, but I need to lengthen the return cable, or trim the cable housing to accommodate the longer throw, so I put it back to stock, for now. I don't like using a single pull throttle on a street bike. When I complete this mod in the future, I will use some adhesive to glue the PVC to the throttle housing.

 

[CAPTAIN AWESOME]

Clever. Definitely doing this in the future.

 

[8ball]

OK, so I finished up the throttle mod.

I very carefully cut of about 1/4" off the cable sleeve using a Dremmel with a cut-off wheel:

Then cut a slit down the section of housing. and that created a bunch of ringlets that had to be removed individually...

I left the end sleeve on and slid it down on the new end oh the housing:

now the pull cable has plenty of slack and adjustment.

Oh and I also performed the Ichiban Moto upgrade, which should be the best performance modification done, so far!

 

[knappyfeet]

Good thinking.

 

[Chuck78]

With the cartridge emulators, that bike should ride quite well. especially with Pirelli sport demons.

looks like you picked up on a lot of great text and common mods for GS's, and your build came out really well in terms of functionality and handling for a vintage bike, without looking like the typical cafe racer build with emphasis solely on cosmetics, often with worst handling "retro" tires than what came stock and out of whack geometry.

 

[Chuck78]

the only thing I could really suggest to your bike to make a drastic improvement in the way rides would be to have some extensions made up to extend the rear shocks to about 340 mm. the 19 inch wheels generate a whole lot of trail, hence the larger offset in the triples than newer bikes. Still, they have a whole lot of trail and could stand to be raised up in the rear and dropped ever so slightly in the front to get a more modern feel to the steering while still remaining very stable.

also, if you look up Chris Livengood, he has a website where he modified those shocks extensively and rebuilds and resells them as functional budget units. he does a mod where he replaces the large top out spring with a shorter spring to gain more suspension travel. This will raise the rear of the bike a bit, and if you do that, you might be able to get by with just dropping the front slightly, and then reap the benefits of drastically improved handling. On the 550, the engine is much narrower than a 750 or 1000, so you may be able to get away with lowering the front a bit more since you don't have to worry as much about scraping the cases when leaning aggressively, where the owners of the big four cylinder GS models find out when they start modding their bikes and riding aggressively or racing that the wider 750+ fours touch down on the stator&ignition covers a bit early when dragging knees.

it still won't be quite on par with your Ducati though, but you will be very pleased at the improvements in this old vintage bike with just a little extra elevation in the rear to steepen the rake and reduce the trail to where they should have been all along.

I'm sure those cartridge emulators and Pirelli tires helped out immensely as well. All around, you will have just about the best package possible. I would have suggested doing the popular twin pot brake mod using Honda 296mm floating rotors and Ninja calipers, but if you get good pads on yours and run stainless lines, they will be sufficient, but there are better mods to do using newer models brakes.

Great looking job overall, congrats.