Long weekend over here is giving me a chance to continue the relentless quest to get this bike up to a fine running representation of this fantastic little sportbike which has spent more time on the lift than it has on the road- but I'm happy there's been no catastrophic issues...no broken rings, or circlipless wayward gudgeon pins or seizing...touch wood.
First step yesterday was to swap out a PGM and in doing so I was excited to find a disconnected wire. A yellow and blue which emanated from the PGM to the harness. Unfortunately research told me that this only affects the rev counter and would not affect the running of the bike.
Like I said a have a few.
Side panels come off again. Note just one strip of duct tape on the radiator to help get the temp gauge needle past 60. The cooling efficiency of this T2 Racing radiator is impressive- when I have been running around on this bike it's been in the high (fahrenheit) 90's...or high 30's in real money
Replaced the PGM, correctly connected all the wires. Out for a quick run and it seems like it's the rear cylinder that is failing to fire well after the 7-8k mark. Strangely, it felt better when it first started but when out on the streets- it was not interested. Later we will see this makes sense.
Straight back to the garage and I figured this would be a good time to put a new plug in to re-check it wasn't just oiling up. No difference. I should've tried a different plug cap- but I had a gut feeling it's the carbs and I'm going to have to go in there. Plus- I've never mentioned this before but the rubber carb insulators I got from Spain must be for an M16 because it took far too much encouragement to get the carbs to fit into their rubber homes so this was a chance to replace those with an MC-18 set I got from Jauce. They are in good condition. No cracks, not as flexible as you would like, so I left them in this overnight which helps restore their pliability.
I've made a few discoveries.
A bit of goo in the bottom of #1 float bowl- but probably not enough to affect performance.
The needle jet holders were in the wrong position...
I had the flat side of the holder towards the intake. In my defense that's how I found them- but you should never ever trust a previous owner has done anything correct.
How I found it back in the beginning
I don't think this is a big deal to be honest....but I found something that might be. In Carb #1 the choke plunger was practically seized in an open position...it took quite a bit of encouragement to get out and you can see it's not enjoying going in or out. Will polish both the plunger and the inside carb walls of where it should go and if that doesn't help will get a bit more aggressive with the plunger and spin it with some fine valve grinding paste.
https://youtube.com/shorts/_w3QcJkjbGU
This is quite strange because this has happened to me before on my Kawasaki H2...to the same kind of brass choke/cold start mechanism AND then, much more problematic- a throttle slide seized in place. I wonder what's happening? First thoughts are the low quality fuel with lots of modern additives but I only use non-ethanol 93 octane.
Anyway I'm excited to discover this and I'm thinking I might be on my sway to solving the issue!
Much labeling of the hoses still needed to remember to get all this plumbing correct in the reassembly
Hmm- airscrew out 2 full turns. Recommendation on this site is 2 3/8....Service Manual is 1.5 Jury's out. I'm going to go back to stock jetting and maybe go with the Serivce Manual of 1.5 since I have the Tyga pipes. No amount of reading and researching has found me anyone brave (or crazy) enough to suggest any jetting alteration to compensate for the Tyga pipes with short cans so I'm going to go back to original jetting and 1.5 turns.
I'm proud to say that I still have the special torx screw heads in the carbs requiring Honda Special Tool 07703 0010500...which CMSNL has for $53 https://www.cmsnl.com/products/driver-bit-tool_077030010100/but instead ordered some hollow point torx heads from Amazon which I'm confident should work just as well and mean I don't have to use forbidden pliers on the heads.
This took me to the coffee shop today. Hand built engine by me, as close to stock as possible, as a 1984 model it's four years older than the NSR and four hundred times less complicated....but as much fun? Almost.
