kicker Posted July 7, 2016 Share Posted July 7, 2016 Yeah come to think of it I think I have the cylinder pairing wrong in my head, so would be sparking 180 out, just use the test procedure above to set it up as it was. Set up your new coils, when you bridge the Black/Blue and Green/White terminals you should get a spark on #1 plug (far left plug if you are sitting on the bike). If #1 doesn't spark and #2 does you can either swap the wires on the ignitor plug or just swap them at the coils. Quote Link to comment Share on other sites More sharing options...
shavenYak Posted July 13, 2016 Share Posted July 13, 2016 Fuel tank seal has been done. Basically spent a whole day doing another round of marine clean, then a good 2 hours of metal ready. Spent a fair amount of time drying it out with the heat gun. End result, meh it actually looks a bit thin at the bottom where all the rust was, and I can see an exposed rust flake towards the top of the tank, so who knows, maybe I didn't dry it enough.. Will run as is and see how we go. Pre-sealant: Post-sealant: And while this was happening... Stripped some more stuff, gave the bum end a good clean to repaint some surface rust. However as I was cleaning up the swingarm, I suddenly noticed what looks to be a big old dent in one side of it. Would this be wof fail? 2 Quote Link to comment Share on other sites More sharing options...
Steelies Posted July 14, 2016 Share Posted July 14, 2016 saw this thing last night, so space age. awesome! Quote Link to comment Share on other sites More sharing options...
shavenYak Posted July 24, 2016 Share Posted July 24, 2016 So I swapped both coils out for a new pair, along with a new set of leads. Had to space out the mounting holes for the coils which were about 10mm too narrow. chucked the fuel tank on and tried to start the bike. Took a while to get it to fire - the choke doesn't feel like it's doing much and I ended up just using my palms over the carbs to choke it. Seemed to work and the engine fired up! revs fairly quickly but doesn't seem to want to get over 5000 rpm. Not sure what's happening, if maybe the cdi is a bit buggered and that's why they piggy backed the other one on? Will take a video of the engine running tomorrow. 1 Quote Link to comment Share on other sites More sharing options...
Goat Posted July 25, 2016 Share Posted July 25, 2016 A couple of theorys for that symptom: Has it got a fully charged battery? Check voltage to coils when revving. It may not be getting enough. (Have had this before) Could be leaning out. CV carbs eh? Diaphrams all good? A Blockage in the Exhaust? (Have had this before) Is there enough fuel flow from the tank to sustain high revs? (Have had this before) Did you try once it has warmed up? Quote Link to comment Share on other sites More sharing options...
kicker Posted July 25, 2016 Share Posted July 25, 2016 ^+1 Dem carbs spic and span on the inside after rusty tank? Quote Link to comment Share on other sites More sharing options...
shavenYak Posted July 25, 2016 Share Posted July 25, 2016 Yeah had another go this morning, seemed to go a bit better. Once it warmed up it started doing some weird stuff where engine speed would go up on its own to about 3000rpm for like 5 seconds. Did manage to get it to rev over 7000, so yeah probably a bunch of crap in the carbs. Was hoping not to have to touch them but yeah might pull them apart for a clean up. Spent the rest of the day reassembling swing arm, rear brake and electrics. Still got quite a bit to do and a big pile of screws and bolts with no real order. Lesson learnt for next time. Edit: here's a video Quote Link to comment Share on other sites More sharing options...
anglia4 Posted July 25, 2016 Share Posted July 25, 2016 when I first bought my CB it wouldn't rev out and setting the floats helped it. Quote Link to comment Share on other sites More sharing options...
shavenYak Posted July 29, 2016 Share Posted July 29, 2016 oh god what am I doing 4 Quote Link to comment Share on other sites More sharing options...
shavenYak Posted August 9, 2016 Share Posted August 9, 2016 So I've had the carbs apart, cleaned everything, reassembled - bike won't run. One thing I didn't check was the float height. when I first bought my CB it wouldn't rev out and setting the floats helped it. So the problem I have now is I can't work out where exactly I'm supposed to be measuring to on the floats themselves. The workshop manual I'm using is just too photocopy spec. I know i measure from the gasket mating face on the carb body, but do I measure to the very bottom (when carb is right way up) of the float? There's a seam right in the middle of the float which seems like it's in approximately the right place.. Oh and I think I've discovered why there was a second CDI wired in - apparently these bikes have a 11k rev limiter, and by using one CDI per coil you get past this. According to these guys anyway: http://retro.400greybike.com/topic.asp?TOPIC_ID=3803 Purely academic at this point since one of the CDIs doesn't go anymore. I'm happy enough with 11k anyway! Quote Link to comment Share on other sites More sharing options...
tortron Posted August 9, 2016 Share Posted August 9, 2016 Quote Link to comment Share on other sites More sharing options...
shavenYak Posted August 10, 2016 Share Posted August 10, 2016 Yeah bottom of float to gasket surface seems to be the standard way. Spec for these carbs is 22mm, at the moment the tang makes contact at around 26mm so it's way too low.. What's the best way to bend these things? I feel like I need to bend it inward so far that I have to bend the other metal tab as well. I guess I'll just bend away and see how it goes - weird that they're both so far out and the bike still ran quite happily when treggo owned it.. Quote Link to comment Share on other sites More sharing options...
tortron Posted August 10, 2016 Share Posted August 10, 2016 having an incorrectly adjusted float will make the carb run richer or leaner. you can make up for that by adjusting the carb, but it will lean out/richen up where you dont want it to Quote Link to comment Share on other sites More sharing options...
Popular Post shavenYak Posted August 15, 2016 Popular Post Share Posted August 15, 2016 Great success!! Big thanks to kicker who came round and helped out with the carbs. The thing that was tripping me up was the little sprung pin on the end of the float valve needed to slot into the tang so the float not only pushed but also pulled on the valve. Pretty obvious in hindsight. Rigged up a pretty flash auxiliary fuel tank from a dishwashing liquid bottle, and fired up the bike. Ran pretty well if a bit smoky, but we couldn't get the idle to sit any lower than 2500. Pulled the carbs off again and tweaked the butterfly balance between the two, and then we fiddled with the pilot screws but still wouldn't idle low. Apart from that, engine sounds great, nice fast throttle response and the smoke had cleared up. Kicker was the Guinea pig/crash test dummy and was happy with how the bike was behaving. So I chucked on my new helmet and went for a ride! Feels great to ride, I'm getting used to the gears, and bike goes and sounds awesome. Spent around an hour riding around but I should probably go get a wof tomorrow before I get into trouble. 10 Quote Link to comment Share on other sites More sharing options...
Goat Posted August 15, 2016 Share Posted August 15, 2016 Good sheet broes! Quote Link to comment Share on other sites More sharing options...
M Night Shamalayan Posted August 15, 2016 Share Posted August 15, 2016 this is savage, man. so jelly Quote Link to comment Share on other sites More sharing options...
kicker Posted August 15, 2016 Share Posted August 15, 2016 Tis a sweet bike, goes hard for what it is Quote Link to comment Share on other sites More sharing options...
Seedy Al Posted August 15, 2016 Share Posted August 15, 2016 That's rad dude! Well done Quote Link to comment Share on other sites More sharing options...
Popular Post shavenYak Posted August 16, 2016 Popular Post Share Posted August 16, 2016 Bike is now legal! Had a good ride around the hutt today under sunny blue skies. Bike still wouldn't idle lower than 2.5k which was pretty annoying after a while. Got home and tracked down a little vacuum leak around one of the carb boot. Screws on the jubilee clamps were pretty munted so I couldn't tighten them enough. Swapped them out for some nice fresh stainless ones. Fixed the leak, but idle problem still there. After some headscratching and removing and reinstalling the carbs for the umpteenth time (I'm getting good at it now), I finally realised what the problem was... ... The choke lever adjustment screw on the handlebars was out. So, felt pretty dumb but also super stoked everything is now running good. Now I gotta get some pants, boots and jacket and go on some epic rides! http://youtu.be/FWmH9ylqYYQ 10 Quote Link to comment Share on other sites More sharing options...
EpochNZ Posted August 16, 2016 Share Posted August 16, 2016 I thought that must have been you tootling through Naenae around 10ish, not many Impulses around these days. I was going to wave and toot to say hi, but then realised it might look like some kind of gang initiation thing... Ev. 1 Quote Link to comment Share on other sites More sharing options...
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