Lord Gruntfuttock Posted October 27, 2023 Author Share Posted October 27, 2023 Last night after work I adjusted the valve clearances and re-routed the starter lead and oil line away from behind the rear exhaust... Had the day off today and had planned an early start on the bike, but it was snowing this morning so I stayed in bed... When the sun came out I hit the shed and: heat shrink wrapped the exposed starter solenoid terminals cleaned the carb, cleaned the air filter foam installed carb manifold, carb and filter, and connected accel cable cleaned genny, fitted oil slinger, new bracket and gasket installed and connected generator. fitted starter motor cover, installed generator breather tied up new ignition wires, fitted footpegs fitted exhausts, fitted kickstarter, discovered starter hits rear pipe removed exhausts, bent mounting bracket, refitted exhaust discovered kicker still hits rear pipe, swore loudly, will come back to this fitted rear brake cable, fitted battery cover traced old points wiring fitted seat hump, found new plugs and put battery on charge Glad I cleaned the filter foam, lot of grease and sand came out of it, just rinsed in kerosene, shook dry and reinstalled... and carb looks much better with the grime removed... So nearly there, big day and called it quits before I made mistakes hooking up the ignition. I looked at my old leads, thought I could use them again as they were good ones, but seems they are spiral wound stainless core, which may not be good for electronic igntn? (I'll read instructions). The kit came with new ones so no big deal, just not the straight plug in swap I was hoping for. So some hopefully simple wiring, static timing and we're almost good to go... 3 Quote Link to comment Share on other sites More sharing options...
GregT Posted October 27, 2023 Share Posted October 27, 2023 I'll make a small and pessimistic prediction - I reckon you're going to have to make another rear pipe. It needs to be higher and tucked well in for rearset/leg clearance and kickstart clearance. The one bit you can't change is the kickstart arc - and any fold up footrest has to be hinged well inside the line of pedal travel. Been there myself before. Luckily a pipe isn't hard to do. 1 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted October 27, 2023 Author Share Posted October 27, 2023 Yeah suspect you're right. Priority now is just getting it going again. Can make do with it hitting rear pipe in the meantime. Rearsets will take some thought, esp as the ones I have aren't folding... Quote Link to comment Share on other sites More sharing options...
GregT Posted October 27, 2023 Share Posted October 27, 2023 I think you're going to have to take your rearset mounts off the available holes in the frame lower castings. Do they call them the hatchets or something similar ? Plenty of aftermarket folding pegs around - usually sold as pillion pegs Edit - A couple of stray neurons collided and I remembered that in HD language those castings are the tomahawks. 1 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted October 29, 2023 Author Share Posted October 29, 2023 Yeah I was wondering what they're for, currently one side is used for exhaust bracket mounting, I've also seen a factory pillion peg bar that bolts up to a plate on the rear engine mount bolts. Progress update: A mixed weekend. Made up new leads (had an MSD clamp former from doing my car) and connected ignition to coil and static timed, used the pencil in spark plug hole method. TDC on front cycinder lines up with dot timing mark, and set ignition to just turn off and locked down as per instructions... Then it got depressing, thought I'd spin it over on the starter to check spark, and just got a rapid clicking noise. The solenoid was banging rapidly in and out for some reason, annoying as I'd just buttoned everything up and thought I was good to go. Tried jumping from another battery and same result, so I called it quits for the day... Next morning after a think and a breakfast beer I pulled the clutch cover again as the only thing different was the thrust washer, and I wondered if it was preventing full throw of the solenoid? No difference, so I pulled the rear exhaust to check starter solenoid resistances again, and pulled starter motor to test, all looked good... Also manually pushed solenoid arm in and out and checked meshing with clutch ring gear, all good as far as I could tell. Decided to fix the things I could, managed to get heaps of clearance for kicker past rear pipe... And I tapped out the positive battery terminal to 8mm, as the 6mm post thread had become worn. Surprisingly on connecting things up again, the starter motor spun the engine freely? Quick test with coil connected and plug held against engine showed excellent spark, so I fitted everything again, plus battery cover, tank and fuel lines. Assumed I'd fixed the issue without finding anything obviously wrong (maybe a bad connection somewhere)...? Sadly, when trying starter again, same problem, solenoid banging in and out rapidly. No idea how this actually happens, it's as if bringing it in breaks the circuit so it rapidly cycles on the spring. Or the voltage dips below that which can bring in the coil, shouldn't be shorting as have fuses in the circuit... Really stumped at the moment. Sprockets move freely, starter arm moves in and out ok, solenoid coils test well, 12V at solenoid from start button, battery at a strong 12.6V. Not sure if it's binding mechanically or the electrical circuit is compromised somewhere. A few things to test yet, I'll try running a 12V lead straight to the starter terminal in case the starter button is faulty, and I'll remove the battery cover and try attaching another battery... So currently perplexed, but on the plus side I'm close, and really good at adjusting the clutch now... 3 Quote Link to comment Share on other sites More sharing options...
GregT Posted October 29, 2023 Share Posted October 29, 2023 Is there a relay in the circuit between switch and solenoid ? Probably shouldn't be but I've seen some odd ways of protecting from high current draw. Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted October 30, 2023 Author Share Posted October 30, 2023 Yeah think there is. I rewired the whole thing, will have to look at diagram. The old harley switches are a known point of failure. 12v straight to starter solenoid terminal should tell me something. Wondering now if it's just the battery failing, maybe starter motor draw drops voltage enough for pull-in coil to drop out... 1 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted October 30, 2023 Author Share Posted October 30, 2023 Update, tried the following after work. [1] Ran a lead from battery positive to the starter solenoid terminal. Exactly the same, solenoid bangs in and out, nothing rotates. Battery voltage drops to around 5V... [2] Hooked up spare battery in parallel with big jumper leads. Doesn't chatter, bangs in but no rotation, smoke from starter motor if I hold it in. Faint whine from somewhere... So have ruled out starter switch and relay as an issue, but unsure on diagnosis. It's like something is mechanically binding, or there is an issue with the starter motor. The starter motor spun up ok when I had it out the other day, but I'll pull it and check brushes as that's probably easiest to start with... Quote Link to comment Share on other sites More sharing options...
GregT Posted October 30, 2023 Share Posted October 30, 2023 Starter motor going in correct direction ? Does it earth through frame connection or one on the engine cases ? 1 Quote Link to comment Share on other sites More sharing options...
Goat Posted October 30, 2023 Share Posted October 30, 2023 Could be a poked starter. One of my ironheads would do exactly this, wouldnt crank, but would spin up outside the bike. Wanged a new (second hand) starter in there and winds over like a champ. I've never had any luck rebuilding starters on japanese bikes. They never seem to work after ive opened them (the bench test fine but dont have the minerals to crank). But these prestolite ones might be so archaic, they might respond well to a rebuild kit?? 1 1 Quote Link to comment Share on other sites More sharing options...
GregT Posted October 30, 2023 Share Posted October 30, 2023 When I was in the shop in ChCh, I always cheated with starters. Very good and clued-up auto sparky 2 doors down the road....Source or make brushes for anything I threw at him. Have seen low magnetism as a cause for low ergs starter too. 1 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted October 30, 2023 Author Share Posted October 30, 2023 Yeah I think I've had it apart before, can't remember if I replaced brushes. I'll start with checking it out as at least that's another thing ticked off if it's OK. And yeah earths itself through tiny bolts to the case. Could try another earth via jumper lead as an easy test. Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted October 31, 2023 Author Share Posted October 31, 2023 Yeah found the problem. Commutator is boogered... Tried starter again with a solid earth direct to starter motor case and was no different (more smoke at motor terminal) so I pulled the motor and applied voltage directly to the terminal with case connected to negative. Just a spark and no rotation, 2 days ago it spun away good as gold. So opened it up to inspect, turns out it's the Hitachi not Prestolite starter going by dimensions, weight, and brush connection type... The brushes are just out of spec, Hitachi limit is 7/16" (~ 11mm)... Not quite sure how the commutator got so damaged but there was a lot of greasy gunk that possibly stopped them making solid contact? They were quite sticky in the brush holders, maybe enough to overcome the springs... So I'll look into replacing the brushes/a rebuild kit. In the meantime I'll see if I can dress the commutator, maybe skim it in the lathe and manually undercut the mica slots... Glad I found something, if the parts will take a while to arrive (normally the case) I may see how it goes with old brushes cleaned up until they arrive, the starter motor is probably the easiest thing to get out to service... 3 Quote Link to comment Share on other sites More sharing options...
GregT Posted October 31, 2023 Share Posted October 31, 2023 I wouldn't skim an old commutator. You risk pulling a segment off.Clean it up with wet and dry paper in the lathe then clean out the slots. 2 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted October 31, 2023 Author Share Posted October 31, 2023 Yeah will try that in the lathe first. See if it's badly scored or will clean up... Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted October 31, 2023 Author Share Posted October 31, 2023 Had a quick look at the armature before work, put it in the Myford and tried sanding first, but was beyond that, so skimmed it lightly to get a uniform(ish) colour across the commutator... Looks better, the chips at the end were there before... And a bit of work to do scraping between segments to clean things up. I'll make a tool out of an old hacksaw blade for this. Still a few dents in the comm but I'll scrape it and clean with solvent before testing to see how things look before making a call on skimming it again. Looked at refurb kits, lots out there but once again I'm looking at $20 cost and $60 post to NZ. Being Hitachi there are a few brush options available locally. I measured them at 6.75 x 10.8mm, and 7 x 11mm brushes are a readily available size, with decent sized side entry leads and notch for spring. These should fit the brush holders ok... For $14 it's worth a punt... 5 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted November 1, 2023 Author Share Posted November 1, 2023 Cleaned up after work, scraped slots out and put back in lathe to sand scratches out, looks ok after a clean... And testing doesn't indicate any major problems, tested each segment to iron frame, all ~ 18 Megohms, and tested each segment to the one next to it, and each segment to the one directly opposite, no open circuits, hard to tell if there are any shorts as reisistance of these windings is so low. Will clean up brush holder and solder in new brushes when they arrive, and test operation... 6 Quote Link to comment Share on other sites More sharing options...
DB8-TypeR Posted November 3, 2023 Share Posted November 3, 2023 Im surprised you dont have a growler to test it properly. Mostly just so you can have a growler 3 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted November 6, 2023 Author Share Posted November 6, 2023 ^ proper old-school machines those things... Been away for the weekend but did a bit last night as parts had arrived, cleaned things up and soldered new brushes in, first one done here. A straightforward job with a larger (hotter) tip fitted in the soldering iron... Of course did this before I dry-assembled things to check fit, and they're all a tad too long, so will need filing/sanding down... Would have been much easier pre-soldering. I need to take around 2-3mm off each one so the springs will fit over the end. Will see how I go tonight, if it's too tricky I'll just unsolder and re-fit. Want to shape the concave surface as well to aid bedding in, might wrap a small round file in sandpaper to do that... Quote Link to comment Share on other sites More sharing options...
GregT Posted November 6, 2023 Share Posted November 6, 2023 Put a disc grinder with a cutoff wheel in your bench vise. It'll work for shaping as well. 1 Quote Link to comment Share on other sites More sharing options...
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