Topic: Keep telling yourself - a restored 750 K2 is an investment

[the-chauffeur]

Moving swiftly on . . .

This'll give you an idea of what I mean be 'harder' - with the crank bolts tightened to 16lb.ft, the crank turns at 50(ish)lb.ft.  BTW that's with the spark pugs out.  That higher figure falls to 30-35 with the crank bolts backed off the 14-15lb.ft.

Is that good, bad, or indifferent?  Seems a bit stiff to me, it strikes me that the smaller of my two torque wenches may be under-estimating the actual torque it's put into the crank bolts . . . (but not by much).  Again, once in motion, the rotation movement is completely smooth.

And more importantly, is the starter gonna have enough oomph to drive that load?

[HondaMan]

Depending on the type of prelube you have on the bearings, the breakaway torque can be high. As soon as it starts turning, it should drop down to a smooth roll, though. If you use, for example, 10w40 or moly "engine prelube" grease, the breakaway will be high. If you use 20w50 or synth 15w50, it will be much lower.

After it has run for about 5 minutes, most of this will wash out and the breakaway will be much lower. This initial run-in time also seats the bearings (even if they were seated before) and makes them round again. Technically, as soon as you released the crankcase bolts before, the bearings went oval. This is normal. The first full heat-up-cool-down cycle (about 15 minutes) will really smooth things out.

Sometimes, the starter won't turn it on initial try after a rebuild or disassembly. I ALWAYS centerstand the finished bike and give it 40-50 foot cranks with key on, KILL switch OFF (i.e., crank until the oil light goes out) before trying anything else, even before setting up timing or the camchain tensioner. This is just something I took away from my roadracing days, but it did make a significant difference in startups.

[the-chauffeur]

Yup - sounds good to me.

As a precautionary measure, I took the bottom off again and switched the bearing journal that had moved with one to the left of it (looked the most likely candidate for an accidental swap while the cases were away).  That was definitely not right.  Put it back the way it was and it did the same as I mentioned above.  To be sure, I tried it with the starter - and over it goes.  No trouble.  Thanks for the pointers on the lube types - certainly explains the friction/stiction on initial movement.  And I'd forgotten that the journals deform/reform slightly as well.  TBH, I'm not sure that the engine is any different now to how it was before I started, but I feel happier knowing that I've climbed all over it.

I'm on little people duty tomorrow, so ain't nothin' gonna happen until Thursday, but hopefully then I can get the engine back into the frame.   
One thing before I do - we timed the valves when putting the engine together the first time, then set the camchain tensioner.  Having taken the tensioner off to do the bottom end work, am I gonna need to re-time the valves, or can I just put the tensioner back on?  Oh, and can that job be done with the engine in the frame?  I can't work out how dumb that question is - primarily 'cos when I tried previously, I couldn't get the rocker cover off while the engine was in, so I'll apologise for it now . . .

Thanks again all; and HM - it's great to know there's a very patient guru out there somewhere.
 
Regards

Neil

[HondaMan]

The valve timing won't change unless you lift the camchain off of the cam sprocket, like with your fingers. So, that should be the same as before. Glad you figured out the bearing shell swap: it's interesting on these cases, how much on half of one bearing size can alter the crankshaft's loading. The shells are only .0004" difference from one step size to the next, but one size too big always seems to be too much on the crank, once they've settled in to one another. The rods: well, that's a little different story. 

The tensioner can wait until the engine is in the frame, although I suspect you'll want to install it and test that clicking sound before then. My theory here: slowly turning the crank with a loose cam chain can cause the cam to snap from one cam ramp to the next, under power from the valve springs. But, this theory can only be tested by installing the tensioner, setting the tension, and turning that crank again to see if it went away...

[the-chauffeur]

Ah - sorry, schoolboy error on my part there.  When I said can it be done with the engine back in the frame, I meant the valve timing - in other words, is there a way of removing the rocker cover with the engine in the frame?  I haven't lifted the camchain up at all.  I guess my worry is that it skipped a tooth maybe. 

I kinda knew that reinstalling the tensioner wouldn't be too great a task - I see now that I worded my question really badly.    Let's not get into the rods right now . . .

I'm sure you'll also be delighted to hear that I bought myself a precision torque wrench (you know, the kind that are individually hand tested and verified before leaving the factory).  Can't beat quality tools.

Reassembly tomorrow.  He says (again and again).

[mystic_1]

I meant the valve timing - in other words, is there a way of removing the rocker cover with the engine in the frame? 

Not unless you have a modified frame.  Otherwise, do your valve timing before you install the engine in the frame, there's not enough room to remove the valve cover once it's installed.  You can do valve clearances in the frame, of course, through the tappet covers.

mystic_1

[the-chauffeur]

Three words.

Poxy.

Bloody.

Coils 


All that grief and aggravation chasing 'round the ignition circuit and it tuns out that the coils are knackered.  I made this annoying (but rather unsurprising) discovery after having completely reassembled the bike and tried the earlier suggestions setting up the points.  When nothing else worked, I turned to the last - and probably least likely - option . . . and wouldn't you know it, they were dead.  Well, I say they're dead;  put it this way, there's no spark when they're connected to the ignition circuit, whereas when I connect a spare from another bike, we spark up.  Shame they're not the kind of spares anyone local is likely to stock.

Close, but no banana. 

[the-chauffeur]

I stand (sort of) corrected.  It's not the coils.  Or maybe it is.  I'm losing the will to live . . .

Found a local breakers with a set of coils, fitted 'em, pressed go and . . . nothing.  Fiddled about with the points again and got a very small spark from one of the coils.  Tried the original coils and got the same thing.  But not both.  And not what I'd call a consistent spark.

Eventually I got to the point where I realised that I don't have enough patience to get past this point - and that every time I mess about with the coils and plugs, I'm increasingly likely to wreck the paint on the engine.  So to put everyone out of my misery, I pushed the bike a mile and a half (a very long  mile and a half, I may add) to my local Honda dealer.  I've told them it needs recommissioning, but I can do everything beyond that.  They didn't laugh.  Much. 

I'll let you know what they say.


And I'm gonna ask for a bike trailer for Christmas.

[HondaMan]

I feel bad that I couldn't get you past the points-and-coils part, as it it pretty simple in real life. Chances are, it's either a grounding problem, like the small green wire that's supposed to ground under the seat or the big ground cable that goes from the battery to the left top rear engine bolt. Beyond that, it could be corroded KILL switch contacts, or corroded BLACK-WHITE circuit connectors in the headlight. If the BLUE-YELLOW wires from the points are good up to the coils, there isn't anything can go wrong down there.

If you talk to the Honda guys, tell them to verify these grounds first, and the +12volts to the coils next. The rest should fall into place easily. That grounding business often gets overlooked after an engine replacement.

[754]

You were within an hour or two of solving this.. especially with the help of the forum..

 sometimes just walk away a few hours or a day...

[the-chauffeur]

My friends, in all honesty I think the only way you could have done any more was to be here looking over my shoulder.  You have all gone well beyond the call of duty.  754 - I know what you're saying, but I feel like I've been within an hour or two for about a week or so now 

Probably the single biggest hurdle (and this may just be perception on my part) is that there are bits in the system I can't easily test - being the coils in particular.  I've tried everything else, but I have trouble seeing past bits that theoretically should work, but don't.  I think I've already said that I'm fine when it comes to mechanical fixes because you can usually see what needs doing, but with electricals, it's a whole different ballgame.

As for the grounding wires, I seem to remember having connected the green one under the seat to one of the battery box fixing bolts; one of the advantages of taking the engine out again meant that I could get the big cable relocated from where I had it before (wrong) to the top rear engine bolt.  But my guess is that if they weren't connected correctly, there would be no lights or camera - as well as no action.  When I pulled the bike apart I cleaned up the coils and wires; they looked fine, but I've taken both sets to the garage and told them to make what they can of 'em.  Anyways, thanks for the heads up.  I'll let the guys know.

So it's now in the hands of people who have half a clue more than me (I hope).  I'm not gonna beat myself up over it - I guess I'll just sign the cheque and put it down to experience.

Just before I sign off, I discovered one other thing to worry about.  Unbelievably, I've found that one of the new spark plugs I put in was wrong (a DPR7 instead of a DR8).  I checked and double checked the boxes before I fitted them, but some clown must've been sodding about with them and messed up the contents  

Unfortunately, both types are the same diameter, so I didn't realise something was off until I pulled them all out at once having fitted them and checked that the engine turned over (using the starter).  Fortunately, I reckon I only turned the thing over an handful of times with them fitted , but knowing that the wrong plug is about 2mm longer than the right ones really makes me scratch my head.  I'm praying that the end didn't come into contact with the piston head - and looking at the plug end, it doesn't look squashed, dented or flattened . . . and the gap is the same as when it was put in.  But it's still not good.

I doubt I'll hear much for the next few day but I'll keep you posted on any new developments.

[HondaMan]

Fortunately, you're working on the "K" engine, so that plug won't hurt anything. On the "F" type engine, which includes the last 2 years of "late K" production, the pistons had domes that would have bumped into that plug.

In the end, being in UK where speeds are habitualy low, you may wish to run the D7E plugs or at least the Nippon Denso X24ES-U plugs (my favorite, like a D7.5E heat), as these are a bit warmer than the stock D8E "hiway" plugs. This will help keep them cleaner. If you go to the Continent (or here, I'll show you Colorado!) and plan on long days of hiway speeds, you can switch back to the D8E type then (or stay with the X24, they're fine for hiway, too).

[the-chauffeur]

Without wishing to sound too crude, TFFT.

[Hush]

Hope you get this sorted soon Chauffeur (by the way I used to be one of those) as its high time you were riding that bike instead of wrestling with it.
Please come back with pictures or better still a short clip of you riding it.

[the-chauffeur]

Oh.  Crap.   

The shop finally took a look at the bike for me, and told me to sit down, before letting me know that the engine needs to come out again.  Yes, really. 

Two things.  The crank bearings/journals still aren't right, despite all of my earlier efforts.  But in addition, it seems as though the gear selector fork isn't where it's s'posed to be.  The guys said that it's not engaging neutral (despite the neutral light coming on).  Instead it's a false neutral that it's finding.  That dull thudding noise is me banging my head on the table.

The upside - if there is one - is that the shop guys haven't charged anything and have suggested I get the engine out and take it back round to them.  They can then get it open, plastigage the journals and order/fit the right ones, sort the selector and put the thing back together, without charging me an arm and a leg for labour ('cos I'll have done all the hard work).  Given that they do this stuff all day, and I've managed to get it wrong twice already, I think I'll take 'em up on it.

Incidentally, I bought a new set of coils . . . just in case.

Bugger.


Neil

[mystic_1]

That sucks to hear Neil but, it does sound like you've hooked up with a good shop.  A lot of places won't even consider working on these old girls, and your shop not only will, but they're actually giving you advice on saving money!

Best wishes
mystic_1

[the-chauffeur]

Hey Mystic

Y'know, I'm kinda getting used to tearing the bike down and rebuilding it again.  Getting the engine out still hasn't gotten any easier - I just take everything I can off of the frame (so that leaves the engine, swingarm and yokes), take it outside, push it onto its side, and lift the frame off.  I'd love to know how workshops tackle the engine extraction, but anyways . . .

Took me about four hours to get the bike down to bare minimum parts today, bagging everything as I went.  I'll pull the engine tomorrow and then run it down to the shop on Monday.  You're right - they're a really good bunch, and fortunately for me, one of the fella's there has an almost encyclopaedic knowledge of Honda's from about 1970 onwards.  Occasionally the jobs I get them to do take a while, but they don't mess about when it comes to advice and help.  They looked a bit concerned when I said I'd take the engine back for them to do the work, but that was only because they don't stock plastigage - and Honda's own costs a fortune.  Things looked up dramatically when I said I'd got my own that I would drop off with the engine.

They also know I can do most of the work myself, and that I don't take the piss, so they're very accommodating.  I'm sure if I asked them they'd pull the engine (for a price), and they're not afraid to have a go at pretty much anything.  As an example, when I asked them to replace the bushes in the swing arm, they found that the old bits were stuck fast - so much so they couldn't press them out.  They needed to weld a bar to the old bushes and then hammer them out.  And how much did they charge for that?  Half an hour's labour.  OK, so I had already pulled the swing arm out of the bike, but even so, I'm sure it took 'em far longer than that.  And they forgot to charge me for the new bushes that they put in.  I thought I'd better remind 'em, but was told not to worry about it and buy 'em some cakes or something . . .

All of that said, I'm now wondering whether I should just order five pairs of bearing journals and replace the whole lot . . . ?

Still thinking.

[Hush]

Totally agree with you Neil, sometimes its just more realistic to let someone who hopefully knows more than you about these bikes to do some of the work.
If it gets you back on the road quicker even better.
At least you have a very good idea of what goes where and that will definately help in future roadside diagnosis.

[HondaMan]

I'm well aware of those swingarm bushings!    If they could weld onto them, it meant they were Honda's steel replacement units, and they get rusted to the inside of the arm. Poor choice on Honda's part: bronze ones are far better and wear longer, even their older Zamac or phenolic ones did, too. Be sure to grease the new ones every 3000 miles, or you'll go through it all again in 10,000 miles. With care, you can pull out the grease zerks on the big bolt and either press in (or drill a little and tap in, then remove the chips carefully) with 'real' grease zerks that will let you get a good grease gun on them. The stock ones are only good for Japanese grease guns. Also, use a synthetic, non-fibrous grease, and put it to it until the old is flowing out around the pivots, to push any water out with it. When washing, don't hit those areas directly with water pressure, to prevent water ingress.

[the-chauffeur]

Now that's good to know.

Another couple of tips for today:

- Don't expect an engine stand to be any use whatsoever when extracting the engine.  They're really only helpful once the engine is out.

- When extracting the engine through the frame with the bike on its side  (lifting the frame over the engine), push-pull wide strips of linoleum around the engine and between it and the frame.  It stops the frame and mounts snagging on each other and the frame slides right off.

The engine will go in on Thursday.  It'll probably be another week or two before there's any more movement . . .

[HondaMan]

- When extracting the engine through the frame with the bike on its side  (lifting the frame over the engine), push-pull wide strips of linoleum around the engine and between it and the frame.  It stops the frame and mounts snagging on each other and the frame slides right off.

...I'm gonna have to try this at least once. I'm too old to lift 175 lb. engines....

[the-chauffeur]

OK - so perhaps my estimate of a couple of weeks' inaction was a little optimistic . . . but no matter, I'm not in any great hurry.

Right, where were we?  Oh, that's right - the engine.  Lack of bearing/journal clearance.  Hmmmm.  The shop finally opened the crankcases last week and had a good rummage around.  I stuck my head round the door on Friday to be greeted with some quizzical looks and questions about what I had done when I had the engine apart.  After assuring them I hadn't really done anything much more than take the bits out and put them back again, they told me that they'd had to order a whole new set of journals. 

Somehow - and God only knows how/why - they couldn't get any indications of clearance on any of the existing journals.  Weird.  Real weird.   Remembering what HM said about journals distorting/oval-ing when the crank is removed, I s'pose that could have something to do with it, but in any event, I'm not about to either a) challenge the shop's expert (and it is) opinion or b) embark on any kind of forensic investigation to find out why.  It certainly explains why the crankshaft wouldn't move when the crank bolts were torqued.

So, they're awaiting delivery of the new bits before reassembly.  Actually, it's something of a bonus that it's taking time - it's given me an extra month or so to get some more pennies together . . . after buying the new exhausts and other odds and sods, the wallet was feeling decidedly deflated.

More news as it's made . . .

[mystic_1]

Glad to hear the project is moving forward again.

What size bearing shells did you install?  I read back in the thread but don't see if you ever stated which size shells you installed.

mystic_1

[the-chauffeur]

Hey Mystic - nice to hear from you.

You probably couldn't find the size 'cos I didn't change them.  I assumed (in the absence of any knocking, grinding or or other strange noises) that the ones that were in the engine when I took it apart were serviceable and so pretty much left them alone.  Which is why it's come as even more of a surprise that there's no clearance.

Very strange.

Still, as I've said before, I'm very confident with the capabilities of the guys who are working on it, so I'm just gonna close my eyes and hand over the credit card when the bill arrives.  It'll be worth it for piece of mind if nothing else.

Now, wheel building/rebuilding.  I've read up on this subject, but I'm still a little daunted by the prospect.  The building itself doesn't worry me that much - I'll take loads of photos and make reference drawings and stuff to take care of that.  What does concern me a bit is getting the tyres onto/off the wheels.  Can I do this in my garage - the bead breaking bit, that is - relatively easily?

Regards all . . . 

[Roach Carver]

braking the bead off the wheel should not be that hard. you will need some tire tools to ease the tire off the rim. if it is stiff, you may want to cut it with a sawz all.