I also noticed the Pulse Secondary Air Injection (PAIR) check valves were not in a very nice condition. Externally they were a bit gunky and corroded, but internally they were filthy and had a lot of gunky oil blocking them up. So I removed them, repainted the covers, and ran all the internal parts through my ultrasonic cleaner to bring them up nicely again. I used cotton buds to clean as much of the check valve body within the cylinder head as I could. All of the parts came up as new and in fantastic condition.I dismantled the starter motor and cleaned it up and polished it to remove a few blemishes on the body before refitting it with new stainless bolts and I removed all of the other sensors from the block to clean them up as best as I could.

I removed the oil cooler which the filter mounts on to and I had that cleaned through the ultrasonic cleaner to make sure it was thoroughly flushed out internally. It was refitted with a new oil filter and new seals of course. And the water pump was removed and completely disassembled to give it a thorough cleaning. There was a lot of calcific deposits in the various corners and edges of the pumps internals so these were brushed out and the pump was put through the ultrasonic cleaner numerous times. The spindle inside the pump was cleaned up and re-greased and it was all reassembled with new seals and new bolts. The pump now looks like new again.As far as the engine block goes, that was pretty much it.

 

In the process of removing all of the hoses and fittings from the engine block (carburettors aside) I noticed the very ends of most of the hoses were starting to split. Structurally they were fine, but I’m a perfectionist and didn’t like them looking gash, so I installed a new complete silicone coolant hose kit with stainless hose clips from AS3 Performance. These were pretty awesome as they were less than half the price of the better known and more popular Samco hoses but did exactly the same job. With any luck these will hold up well and look awesome for a long while to come.During the removal of the engine I noticed the radiator was in a very poor condition. The tank ends were heavily corroded, almost to leaking point and the majority of the fins were bent, weakened and literally crumbling away as I touched them. So I replaced the radiator and cleaned up the fan shroud and fan so they look as good as new once again too.

 

Also during the removal, It was obvious the exhaust header pipes were in need of a bit of a tidy up. They were mechanically fine and were not damaged in any way. They were just a bit rusty and heavily pitted from years of stone chips and road grime etc. I took them off and spent about 2 weeks using rust remover gel and cleaning them down with degreaser to take all the rust off but I couldn’t leave them like that as they would almost instantly rust again so I repainted them in ultra high temperature silver paint. I had them sitting in the garage for a few months ready to refit before I decided they didn’t look very nice in the silver paint, so they had another 6 coats of black ultra high temperature paint to make them good again. I refitted them with new stainless exhaust studs and nuts to make sure they went on ok and I didn’t have any issues down the line. You can see both the new radiator and the finished exhaust headers below. Of course, new mounting bolts and gaskets were also used. You can also see that the coolant reservoir and it’s protective rubber shield were also cleaned up nicely.I replaced the spark plugs and thoroughly cleaned the ignition coils but they were working fine so no need to do too much more with them.

 

At this point, it made sense to take a look at the wiring loom and more specifically, the aftermarket fuel pump that had been cut into the loom. I used my electrical tester to check all of the connections in the loom and could not find any issues with them. All of the relays appeared to be working fine so I really do not know why the fuel pump was spliced directly into the loom.I couldn’t bare having this section of the loom look like this anymore as I was going for the factory standard look wherever possible. However, I was well aware that replacing every odd part with factory standard Honda parts was just not going to happen on a bike that is this old. I purchased a new tourmax fuel pump online with the correct OEM fittings and actually rated for the correct fuel flow needed on the bike. I also sourced the exact gauge and colour wire to replace the entire section on the wiring harness to make it back to factory condition.

 

When I was looking at the area of the harness that the new section of wire would be put back into, I noticed that whilst the internal wiring on the harness was in really good condition, the outer protective covers were peeling off and areas of PVC tubing designed to protect possible impact or wear areas on the harness were becoming brittle or splitting open. So I spent the next few days replacing the whole lot on the harness with newer woven harness tape and multiple lengths of both semi-rigid pvc protection hoses and self-adhesive heat-shrink materials. All of the rubber boots were removed and thoroughly cleaned whilst all of the connectors were fully de-pinned, inspected and cleaned up, with worn pins replaced as required. In the first picture below you can see how I ended up refitting all of the electronics to the harness to make sure it was all accounted for and to get an idea of the layout ready for when I started to strip the harness coverings. (Warning: Many cable ties were harmed in the refurbishment of this loom. Viewer discretion is advised)With it all now cleaned up and re-wrapped in the loom tape, I reinstalled it onto the bike only to find that the harness was tight in a couple of places where I had either put too much loom tape, or not fully considered the angle the loom would sit at, so it got slightly stripped back again and redone maybe once, twice or even four times more whilst it sat on the bike. But that was another lengthy job complete and the harsh reality is starting to loom on me that all I really have left to do is to give the carburettors a quick check over (ha ha ha, that’s a good one), sort out a known problem with the fuel level sender in the tank (by straight up replacing it with a new factory part) and then clean and refit the fairings and rearsets.

 

Oh and one other thing, I spent £120 having the seat professionally re-bolstered and recovered. The new leather covering is twice the thickness of the factory original and it is now sitting on top of an extra piece of firm foam so that the seat has it’s original profile back but is harder wearing and comfier. The underside of the seat was cleaned and treated with trim gel to bring back it’s factory finish wherever possible and the two mounting brackets towards the back were cleaned and polished and had new stainless nuts to hold them in place. The upholsterer that did the work for me actually did a really impressive job of making the underside look better than it was from the factory. The staples seem far more robust and are much more neatly installed. Very impressed.

 

I would use caution when using Stainless Steel bolts in aluminum, particularly in moist environments due to galvanic corrosion.

 

Thanks for the concern. Hopefully that doesn't become a problem as almost all of the bolts were installed with copper anti-seize paste for almost that exact reason.

 

Ok. Lets get to the ugly part. The airbox and carburettors and the ugly flat spot in the rev range.

Taking the carburettors off the bike, it was clear to see that the dealers had done a bad job of fitting them properly when they supposedly replaced the inlet rubbers. The rubbers themselves have small markers on them where the clamps fit, specifically so that the marker points fit into a hole in the clamp. This ensures the hoses are fitted tightly and that the clamps themselves are pointing in the right direction when it comes to refitting the carbs. If they are even a few degrees off then you cannot get the tool onto them through the frame to tighten them up so they have to be fitted properly.

First of all the dealer had not fitted them in the correct locations meaning that the marker points were crushed and the rubbers themselves were squashed or twisted in places. This also meant that the screws were not easily accessible, but seeing as the engine was out of the bike it wasn’t an issue for me at this point.

Second, one of the clamps was not even the correct part and was clearly taken from a similar but slightly different bike, meaning the marker points were never going to line up no matter how it was fitted.

And third, one of the clamps didn’t even have the screw within it so the inlet rubber was literally just pressed on to the inlet and held there by the rigidity of the carburettor assembly. Theoretically this could have caused a big air leak directly into the inlet and made the bike run crap, however I don’t think that was occurring thankfully. I set about obtaining all of the correct clamps from the internet and this is how they should look with the screws pointing in the correct way.





I set about removing the airbox assembly and all of the hoses from the carburettors. I took this photo after I had got a little bit ahead of myself and stripped one of the carburettors.

 

I set about removing the airbox assembly and all of the hoses from the carburettors. I took this photo after I had got a little bit ahead of myself and stripped one of the carburettors.



Once I had got to this stage, I set about doing a single carburettor at a time. Completely stripping them to bare bones, ultrasonic cleaning as much as possible, polishing as much as possible and measuring screws so that I can source replacements down the line.




Stripping out the main jets, I noticed that a previous owner had put different sized jets in at some point as the sizes did not match with what the factory workshop manual was telling me. The manual states they should be size 132 main jets in carburettors number 1 and 4 (the outer carburettors) and size 135 main jets in carburettors 2 and 3 (the inner carburettors). The sizes are different between the four carburettors to account for the lower cooling you get on the inner carburettors so they usually run a bit hotter. Thus, you get an effect that some of the fuel burns off before entering the inner cylinders and so they run leaner and out of sync with the outer carburettors. The larger jets on the inner carburettors combat this by simply adding a little bit more fuel. Companies such as Dynojet do multiple stages of upgrade kits mostly comprising of main jets and needles to lean out the fuel mix and introduce more air/oxygen into the cylinders to burn faster and hotter, thus giving more power. The Dynojet Stage 1 kit for this bike runs size 118 main jets in the outer carburettors and size 120 main jets in the inner carburettors (along with shorter needles though). It seems that a previous owner had possibly tried to do this in some way but had messed it up and had not used a Dynojet Kit.

The bike had size 134 main jets on carburettors 1 and 4 but then had size 132 main jets on carburettors 2 and 3. The sizes are marginally different from the factory standards, but are fitted to the wrong carburettors. So I sorted this all out with an All-***** Racing Carburettor rebuild kit, using factory standard jet sizes and replacing the needles, float needle, idle screws and pilot jets.