The Big Sue resto-mod thread

I've been using these for the past couple of years.
View attachment 262749
These are great tools. I use them for picking up small parts and as small pliers. Many years ago, a friend’s wife worked at a medical supply company and they were tossing many high grade instruments like this. I snagged as much as I could and still use those them today. The stuff you get at big box store, harbour freight etc are usually low end, off shore stuff that don’t work well.
 
I would assume the shims are ground then hardened
I would think grinding a hardened shim may create stresses in that shim who knows.
Not belabour the point, but I would guess that is done in the other order: harden then grind.

I would certainly not be doing this on a belt sander - I'd use a surface grinder as it is one of the few machine tools that can reliably cut hardened material accurately. Because surface grinders have pretty large and accurate reciprocating tables (aka "magnetic chucks"), it would be easy to mass-produce a whole raft of shims to a specified thickness and specific surface roughness.

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Hardening is a somewhat less predictable process which can lead to warping and dimensional changes in the part. So if the shims were hardened after grinding to size, they would likely not be flat and that could put them out of the specified thickness tolerance.

Anyhow - an interesting discussion but as agreed earlier, it is not worth the risk and so I'll be just buying whichever shims I need.

Pete
 
Howdy all: just a small thing but I was on the GS Resources forum this morning and we were talking about leaking petcocks. I mentioned Hylomar Blue sealant which has given me great results over the years - and someone else pointed out that OEM Suzuki fibre petcock sealing washers have a nifty rubber "lip" which makes them seal very well.

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Note the Suzuki part number: 09168-06023 I just checked and Partzilla and Revzilla both have them for around $2.00-2.80 USD / each (about $457.00 CAD at the present rate of exchange).

I am going to get some for Big Sue and see if they also work on the Yamaha petcock mounting screws that we use on our XS650s and I'll report back.

Pete
 
Howdy all: just a small thing but I was on the GS Resources forum this morning and we were talking about leaking petcocks. I mentioned Hylomar Blue sealant which has given me great results over the years - and someone else pointed out that OEM Suzuki fibre petcock sealing washers have a nifty rubber "lip" which makes them seal very well.

View attachment 263721

Note the Suzuki part number: 09168-06023 I just checked and Partzilla and Revzilla both have them for around $2.00-2.80 USD / each (about $457.00 CAD at the present rate of exchange).

I am going to get some for Big Sue and see if they also work on the Yamaha petcock mounting screws that we use on our XS650s and I'll report back.

Pete
If it works, we have a thread in tech tips for it to find a home. Thanks!
I replaced one of mine with copper washers just last week. Metric sealing washers seem impossible to find here locally.
 
If it works, we have a thread in tech tips for it to find a home. Thanks!
I replaced one of mine with copper washers just last week. Metric sealing washers seem impossible to find here locally.
The problem is not sealing under the heads of the petcock mounting screws - it is sealing the actual screw threads and that is why the proper washers must fit the screw threads very tightly.

In fact, if you simply push the washers down over the threads, you will ruin the sealing action. I always "screw" the washers down onto the mounting screws so as not to enlarge the hole in the washer. THAT is why the Hylomar helps - it goobers-up the hole in the washer and seals around the screw threads.
 
The problem is not sealing under the heads of the petcock mounting screws - it is sealing the actual screw threads and that is why the proper washers must fit the screw threads very tightly.

In fact, if you simply push the washers down over the threads, you will ruin the sealing action. I always "screw" the washers down onto the mounting screws so as not to enlarge the hole in the washer. THAT is why the Hylomar helps - it goobers-up the hole in the washer and seals around the screw threads.
For the time being, copper is all I have. I’ll be looking for your update.
 
Howdy all: just a small thing but I was on the GS Resources forum this morning and we were talking about leaking petcocks. I mentioned Hylomar Blue sealant which has given me great results over the years - and someone else pointed out that OEM Suzuki fibre petcock sealing washers have a nifty rubber "lip" which makes them seal very well.

View attachment 263721

Note the Suzuki part number: 09168-06023 I just checked and Partzilla and Revzilla both have them for around $2.00-2.80 USD / each (about $457.00 CAD at the present rate of exchange).

I am going to get some for Big Sue and see if they also work on the Yamaha petcock mounting screws that we use on our XS650s and I'll report back.

Pete
Dowty washers, is what they are. McMaster-Carr and other places have them for much less than the OEM suppliers.
Personally, I just use Hylomar top and bottom of an ordinary washer, as you suggest, and never had a problem with them sealing.
 
Well, it is just a small step, but an interesting one that includes a slick modification I made 43 years ago and a bit of snazzy new 2024 technology.

The Problem
The early Suzuki 4-strokers had just one significant flaw (IMO and that of most of the bike magazines of the day), the charging system was...shall we say, of dubious quality and unreliable performance. Basically, the regulator/rectifier unit was under-rated and unreliable and the alternator itself, particularly on the 1979 GS850G (the bike I had) was not up to the job of keeping the battery charged and running any accessories (it was intended as a big tourer....). The thing to do was to try to reduce the electrical load whenever possible and, aside from the starter itself, the headlight was the thing that drew the most current when starting the bike (the point in time when the reg/rec was most likely to fail).

This was compounded by the fact that daytime running lights on bikes became mandatory in Canada in either 1978 or '79 - and so you simply could not turn the headlight off - no-way, no-how. If the ignition key was turned on, the headlight was on. There was a headlight switch knob on the left-hand handlebar switch cluster on my new '79 bike, but it appeared to be glued in place and would not move at all.

The Solution
The way to solve the charging system problem would be to figure out a way to shut off the dang-danged headlight when cranking the bike. Also, for me, as a serious motorcycle tripper and camper, finding a way to kill the headlight when I wanted to make a stealthy entrance to a campground was another key benefit.

Soooo, a few weeks after I bought the shiny new '79 GS850, I went back out to the dealership (Tony's Suzuki in Kingston, ON) and asked Tony (truly one of the sharpest mechanics I've ever met) if there was any sort of kit or...something that would make it possible to turn off the headlight. Without a word, he pulled out his #1 Vessel JIS driver and removed the tiny little M2 screw that retained the fixed headlight switch knob on the LH handlebar, and took off the knob (see the photo below). He winked and pointed out the little plastic tab that stuck out from the large "radiused" face of the switch knob. That tab engaged with a slot on the handlebar switch cluster - and prevented the switch from moving.

Stock Switch Knob - broken_v2.jpg


He then pointed out a little metal bar that protruded out of the switch cluster on the bars (see the photo below) - that bar is the headlight switch actuator.
NOTE: the photo is of my "new" '79 GS850G - and the switch is shown in the OFF position.

Headlight Switch Lever - OFF.jpg


....and, now back to 1981 - Tony winked as he moved the metal switch lever to the rearward position (shown above) and started the engine.....NO HEADLIGHT - and then once the engine was running, he moved the lever to the forward position and WAH-LA - headlight on.

He went on to say that since the headlight-on thingy was a federally mandated requirement, it would be illegal for him to grind off that little tab on the switch knob, but of course, if someone else did it, there would be nothing he could do about it.

The 2024 Fix - 3-D Printing - Yah Baby!
I am still getting the barn ready for real projects (building a workbench and shelves etc.) but one of the things I noted when I was examing the "new" bike was that the "headlight knob" fix had not been done to it because the knob was absolutely rigid on the bar switch cluster. So, I pulled out my #1 Vessel screwdriver and removed the switch knob, and sure enough, there was the offending little plastic tab on the radiused side of the knob.
As I began to carve the tab off the knob to do the 1981 modification on the "new" bike, a little wedge-shaped chunk of plastic fell off in my hand :wtf:(see above) and so I thought "OK - gotta glue that back on" and continued carving.

Then the tiny little M2 screw rolled off the seat of the bike...and completely disappeared. :yikes::doh::cussing::cussing::cussing: I guess it is now in the land of 10mm sockets and missing socks....somewhere.

Anyhow, at that point, my former student and good friend (now a senior executive at a very prominent Detroit automotive engineering firm...that specializes in very high perf Fords and whose name starts with "R") came over to see the progress, just as I was down on my hands and knees looking for that f@cking little screw.

He said, "Oh heck, I can 3-D print a new knob for you in a flash - total piece of cake. How many would you like and what colour?"

A day or so later, he came over with the new knob shown in the photo below. It is virtually identical to the old one and no carving or grinding is required to make the light switch functional. He told me that it took him about 15 minutes to draw the part with a free-ware CAD program and about another 10-15 minutes to 3-D print it. Also, I went to our IT people and they have an infinite supply of little M2 screws that they have harvested from dead computer hard drives etc. - so I am back in business!
3-D Printed Switch Knob.jpg


This just proves the old adage, "It's not what you know, its who you know AND what you know....".

Headlight Switch - OFF.jpg


Pete
 
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There is one enormous bone-headed design flaw in the '79 switch.
When coming down the twisties on a cold, miserable rainy night, it's perfectly possible for the gloved end of your left thumb to switch the lights entirely OFF, when all you meant to do was change from dip to high.
 
There is one enormous bone-headed design flaw in the '79 switch.
When coming down the twisties on a cold, miserable rainy night, it's perfectly possible for the gloved end of your left thumb to switch the lights entirely OFF, when all you meant to do was change from dip to high.
Correct - and while that never happened to me back with my first '79 GS850G, it sure could have.

Fortunately, I never ride twisties at night in the rain anymore - so I should be OK.

It does, however, point that Suzuki didn't do a good job on this.

I know that Yamahas have the light on-off switch on the RH bar cluster - and nobody should be messing with any of those switches (kill switch, starter push-button and light on-off switch) while riding.
 
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My 75 has a separate toggle for head and tail lamps to draw straight from the batt.
The lights are also hard wired into straight into the alt.
Alt for daytime, Batt for night and when I'm in town.
Rear switch is IGN, Bottom is lights.
Took me a while to figure out from the bat with hi low beam. Before that time just from the alt.
Loads of fun coasting through turns with oncoming traffic. :yikes:
Clutch-rev-coast. Young dumb and full of :bike:. Knutz!
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Correct - and while that never happened to me back with my first '79 GS850G, it sure could have.

Fortunately, I never ride twisties at night in the rain anymore - so I should be OK.

It does, however, point that Suzuki didn't do a good job on this.

I know that Yamahas have the light on-off switch on the RH bar cluster - and nobody should be messing with any of those switches (kill switch, starter push-button and light on-off switch) while riding.
‘79 and later Yamahas don’t have a ON/OFF light switch. It may have been eliminated from the ‘78 Special as well.
 
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