A little progress

[morrag]

Well, the origional Reliant had virtually the same brake arrangement as you do, but with only a drum at the front, but managed to retard the heavier vehicle with up tp 4 people in it!and whilst complying with MOT requirements, your lighter, single passenger, disc braked front, should, if correctly installed/set-up, have no probs. wouldn't you agree? ........Morrag

[morrag]

Regarding the wheel diam. you are using, it's very similar to the standard o/a wheel/profile diam. of a Robin etc. so if you are experiencing high levels of clutch slip being required to pull away, particularly with a lighter "plot" that your trike obviously is, then I would be looking at a clutch problem.......Regards, Morrag

[scannerzer]

Yeh I would but the variable I surpose is the master cylinder I used,a 17 mm Nissan teranno clutch master,near enough what I though would be ok but now I'm no so sure and it's 8 years since I drove the reliant as a car and I can't remember how good they were . These have pasted mot etc ok as well so maybe I'm judging by the standards of modern cars, unfare maybe

[scannerzer]

Regards the clutch I am thinking of changing the pedal ratio to see if that helps maybe a bit more travel will help, thanks morrag give me something to think about

[ROD]

My 2p...Nice looking trike mate.Is it the early carbon or later ballrace thrust? Im wondering if it is adjusted ok if its slipping.If its the carbon one,make sure it is being held off the cover plate with a spring,or it'll wear out in no time.I spent ages getting my clutch pedal ratio right! I made it very light to operate to avoid ankle ache.If you get stuck I can measure my 'throws' on the linkage?

[BikerGran]

My trike has standard reliant drum brakes with a girling 5/8ths master cylinder and I can lock the brakes easily.

[scannerzer]

Thanks Rod ,yes it is the carbon ring type and i have a spring to hold it off but think i may not have explained myself too well . it's not that the clutch is slipping it's that i have to use high revs and slip the clutch to prevent stalling as though the gearing was to high but as the engine ,box and axle all came from the same car this is unlikley so pedal ratio is what i'm looking at. if you could have a measure when you get a chance that would be great,for comparison.

BG i think 5/8  is about 17 which is why i chose what i did but i'm wondering if this is enough to properly pressurise the 2 rear cylinders and 1 front, as morrag said basiclly the same as the car but i dont know what the m/c diameter was or if it had 2 different size sections ,1 for the front and 1 for the rear but at least i know from your experience that my m/c should at least work the rear and maybe run the 2 front discs from the handle bars.

thanks for the input guys it's helping me narrow down what to do

[morrag]

Again, 17mm is near enough to the old 850 Mini master cyl. bore of 0.70" and that serviced 4x7" brakee drums, and I have used that size Mini master cylinder in a similar setup to yours, but prefered keeping rear and front brakes uncoupled and seperate. Worked well for me. So, your 17mm cyl. should be more than adequate.Morrag

[Olds]

Now i can see why Olds built a pick up   had a little trip to the shops today and had to improvise

Regarding brake and clutch I would look to your pedal ratios. My clutch pedal ratio is about 2.8:1 (8.5":3") and is a little fierce, so if I ever remake it I would try 3.4 (8.5:2.5)
As for brakes I also have a 5/8" (15.8mm) master operating only the rear cylinders, pedal ratio 5.3:1 (8":1.5") and can lock the rears. Think about 6:1 is considered ideal.
Personally don't like the idea of liked brakes on a trike. In an emergency situation the last thing I want is the front wheel locking up.
Saying that, other folk are quite happy with linked.

[ROD]

Ok I'll measure it this morning.
 re brakes..if you hit the pedal a second time (ie pump up the pressure) does it stop ok then? If so,you may have to fit a residual pressure valve (holds low poundage pressure in the lines) this is cos the m/cyl could be lowest of all the brake parts and you have to pump pressure up hill.First pedal hit isnt enuf to pressurise right to the cylinders.I had excessive pedal travel ,it drove me bonkers bleeding it etc.Then fitted a rpv problem solved.PITA to have to alter lines though!

[scannerzer]

Again, 17mm is near enough to the old 850 Mini master cyl. bore of 0.70" and that serviced 4x7" brake drums, and I have used that size Mini master cylinder in a similar setup to yours, but preferred keeping rear and front brakes uncoupled and seperate. Worked well for me. So, your 17mm cyl. should be more than adequate.Morrag

that's true Morrag ,i did try to work it out at the time i got the cylinder and thought it should work ok

Now i can see why Olds built a pick up  had a little trip to the shops today and had to improvise

Regarding brake and clutch I would look to your pedal ratios. My clutch pedal ratio is about 2.8 (8.5:3) and is a little fierce, so if I ever remake it I would try 3.4 (8.5:2.5)
As for brakes I also have a 5/8 (0.625)

the brake is adjustable as we drilled several holes when building it so that one won't be a problem but i'll measure the current ratios and post before i change them ,the clutch i think i cad drill another hole without removing it from the trike,i need to put a stop on the clutch anyway as with so much available pedal travel it's easy to press it down too far which will damage the clutch

Ok I'll measure it this morning.
 re brakes..if you hit the pedal a second time (ie pump up the pressure) does it stop ok then? If so,you may have to fit a residual pressure valve (holds low poundage pressure in the lines) this is cos the m/cyl could be lowest of all the brake parts and you have to pump pressure up hill.First pedal hit isnt enuf to pressurise right to the cylinders.I had excessive pedal travel ,it drove me bonkers bleeding it etc.Then fitted a rpv problem solved.PITA to have to alter lines though!

thanks Rod ,no i already have rpv's although i do have a soft pedal,we found the brakes hard to bleed with the cylinders bleeders at the bottom even though i have an air vacuum bleeder and the way we did it was to stand the frame up vertically,not an option now with the engine fitted ! makes me wonder do i still have air trapped somewhere

[ROD]

just measured it ...
The orig drop arm on side of g/box is 145mm c/c,but i extended mine to 160mm c/c
 The pedal pivot is immediately BELOW the footpeg height centre to centre footpeg to pivot= 35mm
 Ive got a footpeg to push my sole onto,not a pad on my pedal,so the pivot point of pedal to footpeg  c/c =155mm
 From the pedal pivot point vertically c/c= 70mm is the take off for the clutch arm.
 I hope you can visualise all that,if needed I'll get a pic later.
 This set up makes for a really light clutch,and a few folks have remarked on this.I wanted it that way cos my left foot suffers from aching generally and also I f the clutch is stiff ,I predicted that as you push your foot down you may tend to lean your body to the left a bit ,therefore you may get  steering 'twitch' as your arms moved a bit.I havent noticed any of this in the miles Ive done.Having run a VERY hard clutch on a modded 100e many yrs ago,I know it gave me back probs to this day tbh..never again!
 

[scannerzer]

think i can ,i'll make a wee diagram with your measurements  and check against mine ,thanks for that

[ROD]

Yes there could be air in the front lines to the disc(s?).I had this also and fitted bleeds at the top of the lines (headset area).Crazy I know,but have you got the rear cyls wrong way round,ie bleed to bottom? (no not piles !lol) I had this on my rear golf calipers and couldnt get the air out of the calipers.They looked ok but werent! Some folks say to reverse bleed the brakes ie from cyls with a large syringe.I tried it but wouldnt work due to aforementioned calipers upside down.
 

[ROD]

Pic of my pedal

A little progress

 
 BTW ..where did you put the rpv? I fitted my one just after the master cyl outlet.