From 107 to 128

[fabiostar]

nice one nick ..... and the pictures of the valves ?????....give us a wee drool...

[tony.mon]

They look the same in photos except they're flat faced.
Same as the ones I fitted.

[sirch345]

David Silver order is expected today and I've just secured the final piece of engine bling - a set of oversized valves.

Rebuild starts tomorrow.

Nice one with the over sized valves

Good luck with the rebuild,

Chris.

[freeridenick]

I got a couple of hours I'm the garage this afternoon and now have two crankcase halves ready to go back together. The pistons took more effort to get in than I thought and the +120 degrees on the con rod bolts is a fair effort for my little arms but it was all surprisingly easy.

The manual says to replace the o-rings when installing the oil orifices but I don't remember any when I took it apart and a quick look at the parts diagram didn't show any.

[tony.mon]

The manual says to replace the o-rings when installing the oil orifices but I don't remember any when I took it apart and a quick look at the parts diagram didn't show any.

From memory they are the two and the dowel on the oil intake filter beneath the oil pump. The only ones you need to include are the oil flow restrictors (small aluminium cylinders with d shape protuberances at one end) which slot into one crankcase half before joining them.

The only other thing to remember is the bearing location dowel on the large bearing behind the clutch, which needs to be properly aligned or the crankcase halves won't pop together properly- don't try to pull them in using the bolts or you will damage the cases.
I mention this in case anyone is going to use this thread to build their own engine- you're already past this point.

[8541Hawk]

I agree as the only ones I can think of are the 3 when get to the oil pump and bits before you install the pan.

[freeridenick]

Thanks Tony and Mike.

I had a look at my digital copy of the manual and that doesn't say anything about o-rings so I had another look at my printed manual and it says Superhawk with 61MBB05 on the front. Phi of the page below. I'm going to ignore it but it would be interesting to know if it's a print error or whether there is a model with said o-rings.


I had a couple of goes at making sure the bearings on both input and output shafts were seated on their dowels properly just to make sure. The other one I think is easy to get wrong is the small pin on the output side bearing.

[sirch345]

What are you (and anyone else who reads this) using for lubricating the main journal bearing surfaces of the lower crankcase I know and can see what Honda suggests

Thanks for the nice sharp photo's.

Rather strange about the "O" rings I agree,

Chris.

[freeridenick]

What are you and anyone else who reads this using for lubricating the main bearing journal surfaces of the lower crankcase

Just using plain oil Chris. I looked into oil/moly mix and concluded it was best if the engine wasn't going to be run for a while but this is going straight back in and off to the Dyno. Lashings of oil will do I think.

I was going to raise this question later in the build, but it seems appropriate now. What do folks recommend for starting the first time after the rebuild? There will be oil on all the right places but nothing in the oil ways etc. I was thinking of just turning it over on the starter with the plugs out to pump a bit of oil round at low revs. I'll probably do a compression test at the same time so by the time that's done I figure I can just fire it up and balance the carbs.

[8541Hawk]

I had a look at my digital copy of the manual and that doesn't say anything about o-rings so I had another look at my printed manual and it says Superhawk with 61MBB05 on the front. Phi of the page below. I'm going to ignore it but it would be interesting to know if it's a print error or whether there is a model with said o-rings.

Those are the 2 oil spray bits for the transmission. I never pulled them out on mine, So yes there are o-rings in there just usually not messed with.

I haven't found an easy way to pre oil the engine. You could run the pump with a drill motor before you install the clutch cover but it is not easy.
The only good thing is that the oil cooler and the engine oiling are separate circuits or you don't have to wait for the cooler to fill before the engine gets pressure.

[VTRDark]

I would use assembly lube on everything. The initial start on any engine is where the most wear and tear is created so on an engine that has not had oil passed through it in the past and more so tighter tollerances for oil to get through, will manually turning the engine over a few times be enough.

[lloydie]

I woundnt connect the plug caps and turn it over to get oil around the engine .
Then follow the start up guide that roger posted a while ago (sorry I have no link)

[tony.mon]

You can get the engine turned over easily enough by removing plugs and using a speed brace on the alternator nut.
You won't teach tickover speed but it will charge the oilways well enough.
Then spin it over using the starter motor with the plugs stuck into the plug caps but just resting on the engine instead of screwed into the heads.

You only need ten or twenty seconds.

Don't spin the motor over with the starter motor just with the plug caps off, apparently you can damage the coils if they aren't able to discharge, according to Haynes.
I've personally done it many times without any problems, but I cant recommend that you do it in case you cause damage.

Now you can put the plugs in and the caps on and fire it up.

[sirch345]

What are you and anyone else who reads this using for lubricating the main bearing journal surfaces of the lower crankcase

Just using plain oil Chris. I looked into oil/moly mix and concluded it was best if the engine wasn't going to be run for a while but this is going straight back in and off to the Dyno. Lashings of oil will do I think.

I was going to raise this question later in the build, but it seems appropriate now. What do folks recommend for starting the first time after the rebuild? There will be oil on all the right places but nothing in the oil ways etc. I was thinking of just turning it over on the starter with the plugs out to pump a bit of oil round at low revs. I'll probably do a compression test at the same time so by the time that's done I figure I can just fire it up and balance the carbs.

Thanks Nick for that information, that is what I have always done in the past just used the same oil the engine uses (new of course), although apart from one car engine most of the engines I've rebuilt have been old British bikes. I can see what you mean if the engine was going to be in storage for a fair time oil might dry up and/or drain down unlike the oil/moly mix as Honda recommend, a very good point.

Regarding the first start up, I would turn the engine over on the starter without the plugs in until the oil light went out (good point Tony re earthing the plugs). I never thought of Tony's suggestion of using a speed brace on the centre alternator bolt, good idea that. I also like the suggestion made by Mike about using a drill on the oil pump, something else that hadn't occurred to me,

Chris.

[freeridenick]

Another few hours in the garage today and it's now all back together ready for the heads to go on. I'm just waiting for the valves so I can get the seats re-cut and them lapped in.

It turned out to be a bit frustrating today. My first error was not fitting the oil seal for the clutch push rod before putting the two halves together. There's a groove where it fits which I spotted after torquing everything up and assumed it fitted in there. So the cases came apart again only for me to find the seal doesn't sit in the groove. Cases back together, an hour wasted and me very hungry.

Back to it after lunch and all was going well until I came to fit the gear shift star, arm and spindle. You can’t do it with the clutch and primary drive gear all in place. . I should have realised but the manual says fit the clutch then gear bobbins then primary drive. When you follow the manual it basically says fit the clutch and primary drive together so I forgot about the gear selector.

More cursing and removal of parts followed by refitting and finally getting it all together.

Front and rear pistions




Dinky flywheel


Pain in the butt clutch etc