Yeah....but not representative of what you have on the GL (No SMC shown on this vid and the PCV on the GL does more).
For sure...
However, that brings up a point.
You said applying the front is not causing lock up.....and there may be a simple explanation for that!
It's not but, I'm not 100% positive if it's causing slight drag or not since I can't feel it.
Front SMC pressure goes via the PCV which is going to limit the pressure to the rear to a preset maximum, and then even bleed it down as more front brake is applied.
None of that happens when you apply the rear, there is no pressure limiter on the pedal MC, hence you can apply higher pressure with your foot than you can from the front...and lock up!
On the GL, when you press the pedal, you engage the middle of the three pistons in the rear caliper, and then gentle pressure (also limited by the PCV) on the two outers via the SMC. So, the pedal directly controls only one piston out of three, one third of the braking power.
The way the Trike is plumbed is as if the GL was applying full pedal pressure directly on all three pistons, awesome, unlimited rear braking power....but also easier to lock up.
But the Trike is also plumbed like if the SMC on the GL were delivering pressure on all three rear caliper pistons as well, so you do get more breaking power on the rear than if you were using front only on the GL.
Exactly....
So the simplest and obvious solution is....don't use the pedal! Drive the Trike just like you would a car, you are getting plenty of rear braking power using the front only, and also safely limited via the PCV to prevent lock up. Just use the pedal for convenience only, at a stop for instance, when you want to free your right hand.
Using just the front would probably do the trick but, if in a situation I know I'll hit the pedal which would cause drag for a while causing the wear on the shoes. With that being said, the drag may not be as bad due to not using pedal braking all the time. Plus, the drums shouldn't be as hot....
However....
This may be difficult if you have years or riding motorcycles and rear braking is instinctive.
Riding this way would be a challenge for sure after riding for 50 years..... LOL
And....
This would deprive you of engaging the front middle pistons with the pedal when you need full front braking power.
Exactly...
No easy solution for that, but what could be done:
1) Reroute the line from the rear MC. Instead of tying it in at the J-Block, Tee it in upstream of the PCV, so you'll get the same pressure limiting function for the rear pedal as you get now when engaging the front.
This sounds feasable but, as you mentioned in #3 difficulty with the plumbing.
2) Or install a separate proportioning valve in the rear line from the MC to J-Block. This would allow the pedal to deliver lower pressure to the rear than it does to the front. This one from Wilwood is adjustable, so you can play with it until you find the optimal setting:
MasterCylinder No: 260-8419, master cylinders, aluminum tandem, combination remote, compact master cylinder, go-kart master cylinder, handle-bar master cylinder, rebuild kits, high volume, hvm master cylinder, tandem, bleeding kits
www.wilwood.com
Available from Amazon as well.
And your friend Bryan at Wilwood even said he sees no reason why it shouldn't work for your application.
Now this in itself, appears to be quite a straight forward install seperating the front and rear. Not sure how all the other components would interact with one another and/or what to remove other than the PCV from the SMC line. I can see that the existing Wilwood valve would be totally eliminated. Only other aspect of the adjustable proportional valve is that it's aimed for use of disc brakes. Not sure if that would make a difference due to mechanical pressure of disc brakes vs drum brake shoes. I would have to say that it would require more hydraulic pressure for the drum brake shoes due to all the hardware. BUT if pressure is a problem, maybe the rear could be split using two of those adjustable valves. Interesting to say the least....
Or....
3) Go for the disks. Easier to modulate when close to lock-up. And it may be easier than tinkering with the plumbing that seems difficult to access.
This would be my first pick from the above.... Mainly because Lehman along with other trike companies went this route. Rear disc brake kits were customized and readily available after the drum to disc transition took place a year after I had mine built. At that time and through the years, I didn't see any reason to switch. I've done a pretty heavy search in trying to find availability and came up empty. Dealers/Shops like M&J Trikes of WV that converted these drum brakes to disc are now gone. That would have been the best case to have this swap done easily. Finding a kit along with full instruction of installation of what was used and eliminated for these first generation non-ABS Goldwings would also be nice but.....
Makes you wonder why there are not more of these Monarch 1s that are locking up? Maybe you have a heavier foot? Change the pedal angle so you have less leverage?
I've had this trike for 19 years and never had a brake issue until I bled and changed the shoes. Best explanation I have for this is that when I bled the lines, I stirred something up plugging a port or hose somewhere. There are so many possibilities of what it could be for example; Any of all the parts replaced so far or a partially inner collapsed/deteriorated rubber hydraulic line. In all cases, it's hard to believe any of these things simply due to the brake working flawlessly before I decided to change the shoes.
Or maybe it explains why so many have de-linked.
I really haven't come across anyone else experiencing brake drum issues like I'm having other than having plugged valve ports.
PS: Missed the simplest option!
Just plug the port from the rear MC to the drums (= disconnect the rear drum line). The SMC would still give you all the (controlled) braking power you need on the rear when engaging the front and you would still be able to engage the front middle pistons with the pedal in case of emergency.
On top of that, you would still be able to operate the rear through the pedal only if you want gentle action, via the SMC. And, surprisingly, the pedal is also pressuring up the rear through the SMC when not moving, so you'd be covered when stopped as well.
Could do that but knowing this trike and all my riding experience, I would need that extra full rear brake stopping power in case of some idiot jumping in front of me.
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