Front Brake System Diagram

[RPA]

Hello all Rocket Fans,

I have nipped across from the Tr1ke section as I need a bit of help and not sure where my Tr1ke Brothers and Sisters have gone.

I started my build many years ago and as I'm sure some of you know it is easy to have a project stall, this is what happened to me. So after my years, I have given up TV for lent and have started again. I am moving onto the front brakes which I assume are very similar to the Rockets.

I was wonder if any of you had a layout diagram for them and if you need one or two reservoirs? I have been looking and in the UK I think you need a switch for brake level (I have seen these built into the reservoirs) and one for applying the brakes so you feed that signal back to the brake lights. I was going for an inline pressure sender unit for the latter.

My plan is to make my own brake lines (in the sprit of a self build) is this a good idea or do you think after spraying brake fluid all over the garage a few times I'll give up and go for some pre-made ones?

As always any help, advice or assistance will be very welcome.

Regards

Bob

[mawdo81]

So on my Sonic I used kunifer (copper nickel) home made lines with pre bought flexi hoses for the last bit to the callipers. I have a single (Ford Focus Mk1) resivoir feeding 3 MCs (Clutch, Front & Rear). The front goes to a T piece then to the bodywork on each side where the flexi then take over. The rears goes to a T piece with a pressure sensor switch to trigger the brake lights. Then to the rear where there's another T Piece to each side (guess you won't need that ;-) ) before, again, flexi taking over at the body work.

HTH

[mawdo81]

The Ford Focus reservoir has the clutch take off higher than the brake so a leaky clutch won't kill the brakes.

[RPA]

Hi,

Many thanks for the information, I'll start looking for the reservoirs and I hadn't thought about the Tee piece.

Many thanks

regards

Bob

[RPA]

Hi,

Many thanks for the information, I'll start looking for the reservoirs and I hadn't thought about the Tee piece.

Many thanks

regards

Bob

[casesensitive]

I had custom flexi lines made from reservoir to caliper an all around.
Though some people have told me it won’t pass an IVA.
I’ll dig out the drawing and dimensions today.

[RPA]

Thank you that would be great.

When attaching the lines to the frame I’m going to use P clips but did people use rivnuts for all the clips or self tapping machine screws?

Ta

Bob

[mawdo81]

I used rivnuts

[RPA]

I need to check but is it brakes lines have to be secured every 100mm or is that fuel lines?

[daydreamer]

I think rivnuts give a more secure fitment when properly fitted.

I think the risk of a self tapping machine screw working loose means that other types of fixing are preferable. Rivets, nut and bolt or rivnuts are , I think, more stable fixings and preferable for securing brake lines to metal panels or box section.

[RPA]

Hello Daydreamer,

Thank you, I was think Rivnuts all the way might be over kill and so was thinking of rivets as I take your point about screws coming loose.

As I get into the brakes I find more questions! I assume you just flared the end of the pipe for the fittings but there seems to be several different types of flare. Does anyone one know if there is a rule in the UK, it seems to be the bubble flare and definitely not the single flare.

Once you have the pipe all sorted and using a screw connection does that seal or do you need a washer or tape? I can't see how a copper washer would help with a screw just on banjos. So do you need PTFE tape or some form of resistance tape due to the corrosive nature of brake fluid?

Bob

[buildityourself]

You shouldn't need tape as the pipes create a witness seal. For banjos you need copper washers. 

This is a useful guide for brake flares/unions.



The key is don't mix the unions and pipe flares types or they might leak. Be careful buying unions.

For more in depth see this 

[daydreamer]

RE Flare type.  I don't think there is a regulatory preference on the type of flare, however the flare should be of a type that matches the fittings.

We used the cheaper type which is not the double flare.  Tooling for a double flare is more expensive.

As "Buildityourself" commented no need of ptfe tape and washers only needed on banjo type fittings.

Some thoughts....

The unions between flexible and fixed hoses probably have more loadings and stresses than may at first be apparent and good reliable fixing is more important here. I think it is important to resist the transfer of flexible hose movements into the fixed lines as they will eventually suffer from stress fractures if they are allowed to move in service.



My thoughts are these;

Rivits are lightest and cheapest. If the fuel lines are not going to be moved or need removal for maintenance then this might be an option.

Rivnuts allow easy detachment and can more easily accommodate T-junctions and similarly bulky components.

Rivits and rivnuts can work blind ( fitment only from one side).

Nut and bolt can be the strongest.



On a trike I imagine that weight is a key issue for some. The trike is so light that the extra weight of rivnuts and bolts vs rivets may make a difference. If you are chasing the ultimate performance and considering spending on fancy bits , carbon fibre this and that to save a few grams then using rivits where you can might be a cheaper way of saving weight.



In my experience, rivnuts can be mighty tricky to fit well so they don't turn when trying to remove the bolt and when it goes wrong getting them out makes a mess of whatever they are fitted to. Using precisely the right drill size is key, you'll probably have to order them in unless you have a drill bit set graduated in 0.1mm increments. Using locking fluid on machine screw fixings is recommended and pretty much essential on a kit car to prevent things vibrating loose. I can testify that locking fluid and rivnuts is a problematic combination 12 months down the line when trying to remove them from rivnuts without the rivnut spinning.



I suppose the advantage with self tapping fixings is that they work blind and can reliably be removed.

[RPA]

Hello Daydreamer,

Thanks for the advice, I have been doing a lot of reading and looking on line so I think I have the type of flare etc sorted out.

As you say I need to make sure I buy the correct type of nut.

I was going to rivets but I just know I'll get it in the wrong place and will have to remove it. My rivnet experience has been 50:50 some a success others less so involving a lot of adult language and a angle grinder to cut off the bolt!! I found some thinner walled Rivets and as they are just to hold the pipes with no force I think they should be good.

Good idea about the correct drill size I'll check that. I'm off to the NEC next week for the Classic Car and restoration show so plenty of chance to buy some new drills :-)

I still not sure about the separation of the rivets, I have seen in the MSVA guide fuel lines are every 300mm but for some reason I think brake lines are 100mm. Does any one know the correct spacing?

Regards

Bob