Can anyone give me any advice on making a wiring loom for my cbr919 mk indy?

its all up and running etc, but the engine bay is an eyesore! so i want to remake the loom as neat as I can.
I've never made one before and im not sure where to start!

I was thinking of having a junction box in the engine bay with a live rail in it, as at the moment there are about 7 cables going onto one post of the battery!
I would also stick in a common earth as they are here there and everywhere now.

I think it may be easier to do an engine loom and a lighting loom separate too?

do i just take a set of cables and replace them one at a time then fasten them all together in a neat run?

Try here....on this forum as well.....
http://www.locostbuilders.co.uk/viewthread.php?tid=169470

I made a full loom for my last track car from scratch apart from re-using most of the plugs and soldering them into the new loom.

I bought my bits from www.polevolt.co.uk (I have no affiliation to them btw) their stuff is top quality and made things so much easier.

They have wiring diagrams for a rally car on their website and I used those, printed them out and deleted the parts I didn't need.

Was really satisfying and all worked first time too

I used one of their modular fuse box systems. one thing I would highly recommend is a decent pair of crimp tools for non-insulated terminals

I'll second Polevolt. they also have some diagrams on their site that are useful. Use as little joints as possible especially solder, crimp joints, each joint is a potential failure. try to run continuous wiring from fuse to connector/ switch to connector.

Try to use as close to the original colour scheme as possible and make notes, label each end.

Ensure you use the right thickness cable. Automotive wiring tends to be better quality than bell wire from general DIY shops. It isnt significantly more expensive, it's insulation appears is thinner but is actually tougher, it's more flexible and harder wearing than most genaral purpose wire and is better suited for the rigours of a car environment.

Trial fit wiring for length, loosely tapes wires in batches so you can establish the right lengths to cut to. Work out paths round any obstructions and make sure wires going in the same direction take the same route (rather than one of them going the wrong side of another cable). Fix cabling where you can especially for long runs and where a large number of cables are batched together in one point. Where there isnt a suitable mounting point you can cable tie to it would be worth using fixing clips such as 'p' clips.

Leave some slack for all wires to the dashboard so it can be unbolted and pulled forward. This should be done so there are 1 or 2 'batches of cable held together with tape or small cable ties as 'umbilicals'

Avoid overuse of lucar / spade connectors. They are great for actually connecting to fixed items (e.g. switches, light units, instruments etc) but for joining wires to wires always make a solder joint and use heat shrink tubing over the join.

Thanks for the replies everyone

I will look into ordering some bits over the next two weeks while I am at work and then start tackling it when i get home!
As for the slack in the dash wiring, I was going to find some large connectors/plugs so the dash can literally just be unplugged and removed if needed (planning to get a carbon dash in the furture)

Good thread and article Snowy, I have had a quick read but will give it a through going over shortly

Nice introduction to some basic wiring snowy2, don't know how I missed it first time around but there you go.

I completely agree with you about the old scotch lock style through splices, they work for a while then the corrosion starts to set in and hey presto dodgy connections.

A few things stick out in my mind though, the first one being solder joints. Yes they are better than scotch locks.....ish..... but they do come with their own problems. Adding solder creates a stiff joint making it prone to fatigue. If the harness is well clipped and it is kept straight you will probably have no problems at all, but if that length of harness is prone to movement or subject to high vibration you may find that the joint will give way.
A good quality butt splice with heat shrink (preferably adhesive line heat shrink) would be my suggestion and try to keep the splice as evenly loaded as possible, i.e. don't has a single wire in one end and ten in the other. Sometimes this means thinking in advance about where you are going to put each splice but it will make your life easier in the long run.

Secondly there is the use of chock blocks. These were designed primarily for use in domestic wiring and whilst yes there are automotive versions, there is a reason you do not see them on your average Toyota. Domestic versions are a loose fit inside the plastic housing which allows movement to occur. Inside a house this is not a problem, in a car with plenty of vibration and constant temperature cycling the screws do not always stay tight. If you use them, keep them accessible as you may want to check on them every now and then.

I would third the use of Polevolt and would also suggest;

http://www.altecautomotive.co.uk/
http://www.cablecraft.co.uk/

Similar companies and products

thanks

My work bag is slowly filling up with goodies that I'm finding that I need to do this, which should save me a small fortune!
my shopping list on polevolt was arounf £70, now it is down to £38

just hope I dont go over my weight limit for the chopper when it comes to home time

its a shame polevolt dont supply 30m reels of the 11 and 16A thinwall, I doubt I'm going to need 100m of each! or am I ?!

Solder joints are OK if used correctly, they are good for butt joints to join two wires together and even on the Mondeo i scrapped recently (lovely engine and the car cost me £100, i got £75 for it when i weighed what was left of it) had soldered joints in the loom.
The chock blocks were always intended to be a temporary measure on my first loom. and i forgot about them some four or five years later and some 18000 miles on my fist car i figured they were fine. that car is still on the road, with the same loom some 23 years later, the present owner claims not to have issues with them.
i am working on a newer version of the article which uses spade connectors, as lots of folks have "issues" with chock blocks......

[Edited on 7/2/14 by snowy2]