Final Assembly & Wiring

It has been a busy week with some good progress. I didn't quite get as far as first start as originally planned due to fuel pump issues but all the same I am happy with where things are now.

First off, my carb/throttle bodies were finished with machining. Pete Walker of PB Machining based in Loughrea (pbmachining@gmail.com) took on the work and I'm very happy how they turned out. It was invaluable to have someone who understood the final application and who was interested in the project to do the work.

Finished throttle bodies with some re-assembly required

Once I got the finished throttle bodies back I could work on the injector & sensor harness. As the majority of sensors (TPS, MAP, IAT & CLT) are located on and around the throttle bodies, the plan was to terminate the main loom just before it reached the throttle bodies and then have a separate harness that would stay with the throttle bodies for the injector wiring and sensors.

Injector harness

Once the throttle bodies were fully re-assembled, I needed to set up the TPS mount. I had asked Pete to drill and tap an axial hole into the end of the #1 throttle rod to take an M3 machine screw. I took the head of a button head screw down on two sides to allow it to slot into the TPS. I needed to position the screw in such a way that the throttle could move through its full range of movement without reaching the limit of the TPS. Once a suitable position was found, the screw was thread-locked into the throttle rod with a half size nut to provide additional security. Then I drilled and tapped the TPS mounting screw holes in the adapter plate in the right place.

Detail of TPS screw

TPS in place

 
Once everything else had been assembled, I could mock fit the throttle bodies to the bike and complete the injector harness.

Completed Injector & Sensor Harness

Injector placement in the throttle bore

The finished assembly is very tight in the bike. There is not a lot of room to play around with in there and the fuel rail only barely fits between the frame rails. I also had to move the thermostat housing down c.20mm to allow the fuel rail to fit. Even so, it takes a fair bit of maneuvering to get the whole assembly into place and sitting into the intake boots.

All in place. Notice no slides

Some idea of the space constraints

That was the point when I was planning to flow test the injectors and go for first start but the fuel pump decided to give up the ghost. I had tested it previously but this time it refused to budge at all. Investigation pointed towards a short out between positive & ground within the pump. The investigation inevitably lead to this situation:

I may be able to to get the pump going again but for now the best course of action is to just get a replacement pump.

I have confirmed that all the sensors are now talking to the ECU properly. All that's left now before attempting starting is to replace the pump and determine injector flow rates & dead times.

Despite the setback from the pump, I'm very happy with the progress of the last week. Hopefully the next update will be with the bike running.

Throttle Bodies

Sneak preview. :) The fuel rail has not been trimmed to length and the brackets to hold the rail in place are being worked at the moment but you can get the picture.

Petrol tank and pump

I now have an mc22 petrol tank complete with inbuilt fuel pump, filter & pressure regulator assembly.

Using the mounting flange which I cut from the ZX6R tank, I cut a hole in a spare mc22 tank and welded the ZX6R mounting flange in place. Pressure tested for leaks and all is good. The tank will need a clean out before use but is otherwise ready to go.

Flange welded in place

With pump installed

TPS mount & plumbing

A little more work on the project over the weekend. I have fabricated a mounting plate on which to mount the TPS to the end of carb #1. This is simply a 3mm aluminium plate shaped to incorporate the TPS mounting holes and fixed to the carb through the top clamping rod and by way of a threaded hole into the side of the float bowl chamber. The clamping rod end needed an additional 3mm spacer in order to bring it level with the float bowl chamber.
The movement of the throttle will be transferred to the TPS through an M3 bolt whose head has been ground flat to fit in the TPS. The end of the throttle rod will been drilled and tapped to take the bolt. To fix the position of the bolt in place, both a locking nut and thread locker will be used.

TPS mount plate

TPS in approximate position.

The fuel pump mount has been cut out of the ZX6R tank ready for transfer onto the spare mc22 tank. It seemed a pity to cut up a perfectly good tank but all for the better!

ZX6R fuel pump flange

A mock mounting of the throttle bodies and fuel rail revealed that there was interference between the fuel rail and thermostat housing. Fortunately, I was able to overcome that pretty easily by adding an 18mm spacer underneath the thermostat housing mounting bracket. That pushed the thermostat housing down low enough to provide clearance for the fuel rail.

Fuel rail mock fitting (very approximate)

Ideas to deal with plumbing to the fuel rail have been run through also. The first option was to use standard threaded -6 motorsport hose fittings on one end of the fuel rail. That would involve a threaded adapter to sit into the fuel rail end. A 90 degree swivel fitting would then be threaded onto the adapter and lead onto the hose. The issue with this setup was side clearance on the fuel rail. The adapter and 90 degree fitting would need c.50mm end clearance to fit between the fuel rail and frame, which was not available.

The second idea was to run the same type of setup but with a 180 degree swivel fitting threaded into the bottom of the fuel rail and back on itself up towards the fuel pump. A quick CAD mockup of the carb bodies with blanking plates, injectors and fuel rail installed showed there wasn't the clearance available for this either.

CAD mockup of injector and fuel rail position relative to carb body

The final (hopefully) solution is to run a banjo bolt into the end of the fuel rail and clamp the fuel hose onto a barbed fitting. This would achieve something similar to the first  option but with less end clearance required. The other end of the fuel hose will be clamped to the original ZX10R fuel hose fitting to allow it to clip onto the fuel pump.

Throttle bodies & wiring

A new year brings with it a new approach again and some good progress. First the throttle bodies.

The plan to fully modify the existing carburetors to become permanent throttle bodies has been changed again and simplified. While putting the exact modifications required down on paper, I discovered that there is not enough wall clearance in the carbs to fully bore out the step in the casting that forms a small part of the venturi. That realisation then snowballed to simplifying all aspects of the modification.

• Instead of interference fitting a block of aluminium into the slide orifice and machining out with the rest of the bore, I will now bond the original slides in place, fill them with high temperature epoxy resin and take them out to match the carb bore by hand. 
• The main jet protrusion will be drilled out and smoothed out using epoxy.
• The protruding float bowl pieces will be cut down to the level of the float bowl mating surface
• New blanking caps will be made up to fit where the float bowls once fitted and an additional piece fixed towards the front of the carbs to allow for good injector seats. This will become clearer in photos.
• Any imperfections and gaps between the carb body and the new blanking plates will be filled with temperature resistant JB Weld.
• The only professional machining required will be to drill and bore the injector seats in the throttle bodies and the fuel rail.

The major advantage to the new (again) approach is that the majority of the work can be done using basic tools and so can be done quickly. Even better is the fact I am already pretty much ready to send off the carbs and fuel rail to machine the injector seats. Photo's of progress so far below.

Float bowl cut down to seat face

Mock up of float bowl blanking plates

Detail showing infill of gaps with JB Weld for injector seat

Slide filled with JB Weld

Rough filling of drilled out needle jet

I have also been tidying up the wiring somewhat to make it the entire setup more permanent. More to go and there's not a whole lot to see anyway but some idea of what the old CDI area currently looks like is below. Including resistors hard-wired inline into the VRIN wires.

Slow progress

Since getting ignition control sorted, progress on the project has been very slow. Mainly due to work commitments, holidays and spending time on other projects.

The main restriction to major progress has been the throttle body modification. I have switched my tactic again and decided to modify an existing bank of mc22 carburetors to act as throttle bodies rather than to modify the GSR throttle bodies to fit the mc22 engine. This would consist of machining out the carb venturi to create a smooth, unobstructed passage from carb inlet to butterfly valve, also blanking off the slide passage and float bowl and machining injector seats into the bodies after the butterfly valves. The advantages here being that the machining involved is within the scope of my own abilities on a manual machine simply because I don't trust other people's QC!
Since last posting I have procured a spare set of carbs to be modified and am currently trying to find a workshop I can use in my spare time to do the work.

As well as carbs, I've procured a spare fuel tank that can be modified to take an in-tank fuel pump and also procured the fuel pump from a Kawasaki ZX636R.

In the meantime, I have begun to tidy up the wiring loom to a more permanent standard using proper wiring connectors. A lambda sensor has been connected to provide input to the ECU.

I have also wired in the Koso dash into the existing loom and now have a fully functioning rev counter which takes it's input from the ECU. Installation on the bike was pretty straight-forward and consisted of some minor modification to the mounting bracket supplied with the clocks and bolted onto the old clock stay bracket. Wiring was also straight-forward with the majority of inputs being supplied through the stock 9-pin connector for the old clocks. This tidied up the wiring a nice bit as the additional inputs consist of

• Constant 12V
• Switched 12V
• Fuel sensor
• Coolant temp
• Oil temp
• Speed signal

Koso mounting bracket installed

Koso dash installed

Main wiring connected. It is still a mess to be tidied up closer to completion

I'm also trying to get the CBR600RR stick coils to fit but having issues with cylinder #2 clearance with the fan motor. The coil itself is just too long and sticks up too far. Anyone know of stick coils that are just 15-20mm shorter than those on a 2007 CBR600RR?

First ride on ignition control

Delayed a bit getting this up so apologies but things have been slow anyway and haven't been getting a lot of time to work on the bike.

First impressions of riding the bike after sorting out the RPM synch loss errors are all positive! The bike revs cleanly and pulls strong all the way to the limiter. I cannot say for certain if that is all due to the new ignition advance curve as I have been running open carbs for testing purposes. (Couldn't be arsed removing the airbox every time I had to go at anything near the carbs basically)

The ride has confirmed that the ignition control is now working perfectly so its ready to progress with the fuelling side of things. Thats a side that needs the most physical work done in terms of pump installation, throttle body manufacture/modification and full wiring so that may take some time yet. I neglected the fuelling side also as I didn't want to use money and time on it only to find the ignition wasn't feasable.

Data log extract from ride showing rev limiter