1980 GL1100 work in progress

[Paddymcc]

Hello all,
I recently bought a part-restored GL1100. In the UK I think it was sold as the GL1100KA whilst the same model in the US is the GL1100 Standard. It was first registered in January 1981, but it is undoubtedly a 1980 model.
I seen it running at the point of purchase however it now won't start, a solenoid problem I think.
Anyway, I have decided to start work on the brakes first, so if/when it is running, I will be able to actually stop when I trundle it around the parking lot.
The previous owner did a lot of work on the bike back in 2003 but then just left it standing. The front left calliper had no pads, shim or pad retaininers. The bleed nipple was rusted and seized. The right calliper had fewer missing parts but was also bone dry. Both pistons look ok and are within tolerances. The front master cylinder piston was under size, however the master cylinder bore looked pretty corroded so I have gone for a pattern master cylinder assembly. Once the parts (pads, shims, nipples, seals etc) have arrived and with new brake hose too, the front should be pretty well sorted.

 

[Paddymcc]

However, the rear master cylinder may present a challenge. I can't seem to source one and it is in pretty poor condition. I will try and clean it up, but I am not so sure it'll be any good. Some photos attached, I would value your opinions....

 

[joedrum]

it looks bad ...you just have to go after it and try to save it ...as opposed to do nothing with it ...you will get it clean and useable or for sure see thats its toast ...there are many ways around problems like this ...id just stay at it in good frame of mind and take on what comes it looks like it will be a nice bike if you stay with it and dont become the weak link in the project :builder: :mrgreen:

 

[slabghost]

Might be able to source another in better condition or adapt a newer master.

 

[ekvh]

Have you tried Wingovations in the UK?

 

[Paddymcc]

Have you tried Wingovations in the UK?

Actually I have just ordered some stainless steel calliper pistons from them. I have been in touch with a guy who previously sold me a grab rail and a rear fender, he may have more parts....

 

[Paddymcc]

Hi all, an update

Having decided to try and get this old girl rolling again, I decided I would first of all turn my attention to the brakes, on the premiss that if I do get it going, then I really would like to be able to stop, rather than crash into the neighbours' cars.

On examination I established that the entire system had been left dry. Not a problem on the front as at least he brake lines had been left connected and so disassembly wasn't too difficult. Only the front left had pads, the rest were missing pads, pad retainers etc. No big deal, these should all be replaced at service anyway. The front master cylinder piston was below service limits so I actually got a complete pattern brake lever assembly from David Silver for £20, about a fiver less than a new piston kit alone. However I have since heard from Mr Silver, that they sent me the wrong one - good job i hadn't fitted it yet.

On the back brake the calliper piston was totally seized. It had been left without being connected to the pipe and master cylinder and whilst the fluid feed had been closed off with a bolt, this wasn't enough to stop the fluid drying up, crystallising, and seizing the piston in place. Even 110 psi through the compressor wouldn't shift it. However, after 2 days in WD40 and then a 10 min boil, it moved enough to get some mole grips on it. Some lateral twisting, then back to the compressor and pop! It is now out. The rear master cylinder is another story, the push rod that links to the pedal is beyond recovery and it is proving to be a hard part to source. I can get a second hand complete master cylinder with push rod from the US for $87 from https://www.straightwings.com but it will still need a master cylinder rebuild kit, another £25. So I have opted to buy a new "universal" rear master cylinder at £21.99, the trouble is the 45 degree mounting. Most universal ones allow them to be mounted vertical or horizontal, but not at 45 degrees. I will either get a bracket made up or I will harvest the push rod and rebuild the original master cylinder.

I am going a bit Rolls Royce with the brakes, Goodridge lines, drilled discs up front so I can stop in the wet, and stainless steel calliper pistons from https://www.wingovations.com.

The weather has prevented me from doing any work since the calliper strip-down, so I have mostly been sourcing and buying parts. Once the correct front master cylinder arrives, I will tackle the front brake. Hopefully by the end of February if the weather is a little kinder.

 

[joedrum]

well your off and going ..ita amazing how much it can cost to get brakes going sometimes and be confident in them ...your really doing the works to it ....great plan it seems to me so far ....

 

[dan filipi]

And adding some sex appeal is a nice bonus :good:

 

[Paddymcc]

Hello all, well since my last report the weather has remained quite poor, thwarting some of my DIY motorcycle mechanics. Additionally I have had to work two weekends in the last four, further impacting on the ability to get things done.
However, not all is doom and gloom. I installed a much needed work bench with vice in the garage, and I have ventured into the world of bead blasting to some effect.
As you remember, the brakes were poor, having been left without fluid for about 10 years. Some elbow grease with a dab of brake fluid followed by a go in the bead blaster resulted in the following:

 

[Paddymcc]

The bead basting was quite easy although it is a very messy process. I built my own blasting cabinet from a large plastic box, some Perspex and a BBQ grill. For aluminium parts you need to use glass beads or similar media so you don't damage the parts. For steel I have some meal oxide grit. The only trouble is my compressor is a wee bit under powered for his kind of work. I have fitted the new drilled front discs, but that's it. I hope to crack on this month and get a little further. See my next report a the end of March.

 

[slabghost]

If you connect a shopvac to your blaster box you can see better what you are doing with the dust being pulled out by the vacuum.

 

[Ansimp]

A couple of rubber gloves and an air filter as well as slabghost's suggested shop vac and your blast cabinet would be the same design as my commercial one

 

[Paddymcc]

At last I have had some spare time and returned to the GL1100.
Having cleaned the brake callipers the next stage was some aluminium primer and then a top coat of satin black.
Then it was time for the complete rebuild with new retainers, springs, shims, pads, pistons, and rubbers.
Finally, I replaced the brake lines with Goodridge braided hose, and fitted a new pattern master cylinder and brake lever assembly.
Some problems though, the bottom left calliper support bracket stripped a thread. I have re-cut the thread and the bolt, but it still won't tighten. I have it loctited in position right now, but this will need replacing.
Also, having bled he system thoroughly, I just couldn't get pressure at the lever. Some patient pumping was required to get the pressure up, but after about 5 minutes, he front brake was fully functional.
This meant, I was now able to lock the front brake and exert some pressure on the forks for the first time. I pumped in 20psi, and gave it a good up-and-down pump to feel the springs, oil and air doing their bit. And lo, of course, the forks leak.
So, I now have another little problem to deal with.
In the mean time, I have ordered some new Hagon shocks for the rear and have at last sourced a genuine Honda rear brake master cylinder. The rebuild continues!!!

 

[WindNWing]

Very nice work. :clapping:
I was able to fix a leaking fork seal by trimming a sheet of plastic to the shape of the sealmate tool.
https://www.sealmate.net/
I was surprised to see how much gunk was trapped between the dust seal and the nylon washer above the fork seal. I cleaned all that out and followed the instructions in the video and no more leaking.
Ahhhhh..... burp the air out of the forks first. :rant:

 

[Paddymcc]

Thanks for the tip, I'll try that! :thanks:

 

[slabghost]

Super find Gary. I got a few forks to try that on! :mrgreen:

 

[Ansimp]

Almost there! :good:

 

[Paddymcc]

I couldn't get the fork tool to work, so....
I priced up the cost of the internals from David Silver spares and it came to £73! So I decided to see what local services were around and I came across Brook Suspension, offering a full rebuild service for £99.

So, rather than order the parts and put myself trough the stress of dismantling the forks, I decided to use their services.
The forks came out...

The guy in question, Dave Brook, did a great job...

And pretty soon the forks were back in with a second hand front mudguard. Ok, so the mudguard isn't the right colour, but at least it is the right type and better than the 1970s chrome job that was on before.

I have also fitted the new rear Hagons

Next stage is the back brake using the master cylinder that i got from eBay for £15, a bargain.
More soon (probably, I need to do some riding too :moped: ).

 

[AApple]

goodjob

• AApple
• Jul 8, 2013

:clapping: :good:
Love to see an Oldie comin back to life!! opcorn: