Hi,
LM1. Pressing the rear brake lever by hand there is resistance but you can still turn the front and rear wheels. When you ride its pretty ineffective. Have previously replaced rear caliper pistons, seals and pads. Have just bled the left front and rear again- not fully but fluid that comes out has no air bubbles but its still just as bad.
Do I need to go back and completely rebleed both calipers? Anything else I’m missing or need to check or look out for?
Thx
Eddie
Try adjusting it at the brake lever 
It can be difficult to bleed the linked system.
You didn’t mention bleeding the manifold but this needs to be done. I start with this, then rear and then front. I usually have to go through it several times. I know some people remove the rear caliper and raise it to help any bubbles to escape.
The key is to feel how spongy the leaver is.
Good luck.
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Thanks Phil. Tomaseli rear sets. I cut about 10m of thread off the linkage and reconnected and I can get more leverage and just about lock the wheels pushing right down with my hand. A lot better. Will test run and check this morning. Probably needs a tad more though.
Mr P- Manifold? Master cylinder? Proportioning valve?
Thx
Eddie
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Look under the l/h side panel. There’s a doodad up there that should have three hydraulic lines and the hydraulic brake switch in it. There are two types; for ease of identification one has a bleed nipple in it (that’s the ‘proportioning valve’) and the other doesn’t (usually known just as a ‘brake splitter’ or ‘brake manifold’). From memory (and therefore subject to correction), the brake splitter diverts the brake pressure 60% to the front and 40% to the rear. The proportioning valve splits the pressure 60/40 initially but as the lever pressure goes up, that 60/40 changes in a linear fashion to 70/30 controlled by an internal diaphragm. So… lecture over 
The proportioning valve is subject to corrosion and jamming up of the diaphragm. The bleed nipple also corrodes in and breaks when you attempt to loosen it. I think Guzzi realised that they had a good idea too far because I’ve only ever seen it on the 1000SP, G5 and IdroConvert. With these, the bleed sequence is proportioning valve, rear caliper, front caliper. If you have one (possible if a PO fitted it), I’d swap it out for a brake splitter.
For the other, far more common version, the bleed sequence is rear caliper, front caliper.
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Little bit of ‘magic’ that we’ve invested in at the Smithy is a, well, it’s a ‘personal massager’
No, not one of ‘those’, it’s a rechargeable one with various screw-on heads to ease aches and pains.
Getting excellent results using it to agitate master cylinders, calipers, solid splitters, along with bleeding to remove stubborn bubbles and return brake systems to good performance. Was only about £20 from Lidl.
Handy thing to have in the tool arsenal.
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Thanks all. Lots to think about there!
Will have a spin tomorrow. Parts manual just shows a splitter with no bleed nipple so I’ll probably just bleed the system through again. Front brake resovoir a bit gunky so probably need to go through the whole system and check pads and the other pistons.
Great advice as ever.
Regards
Eddie
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The LeMans 1 didn’t have the proportioning valve, just a manifold that connects the various pipes to the front and rear calipers.
Have you fitted a new seal kit to the master cylinder under the right hand side panel?
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Not yet Don. No visible leaks from the M/C but its on my suspect list. I’ll do a full bleed and get serious afterthat.
Thx
Eddie
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Sorry for the bum steer on bleeding the manifold. I assumed because of its high position it would have a bleed nipple.
To clarify the manifold or splitter does not change the pressure to front and rear. The braking distribution is down to relative piston and rotor sizes.
On other bikes with the proportioning valve, SP,G5 and Cali 1100, there is a spring loaded piston which kicks in at a certain pedal pressure and this varies from model to model. They are not interchangeable but I dont suppose in practice it makes much difference. Again this relates to pressure and braking distribution will be affected by piston and rotor size eg the SP has a much larger rear piston.
This is from the 1100 manual
Not had a go at doing it myself yet. but mine work pretty well - CX100. Guzziology does not refer to any issues and has a guide on how to bleed them, if you can get in touch happy to copy the pages and send them to you. Dave R