Author Topic: Seeley Honda CB750F - SH7-655F - - the rebuild starts (Read 14401 times)

01Thomas · « **Reply #50 on:** May 19, 2015, 02:08:06 PM »

Busy...yes...

I also fitted the mainstand. My philosophy is that although this is a sports machine, I ride on the street not on the racetrack, and a mainstand is a nice thing to have, even if it weighs about a kilogram. This stand is heavily modified to make clearance for the Yoshimura-style 4-1 exhaust - these mods show up quite well in the photos!

I have also fitted the front wheel with it's mudguard and the refurbished brake callipers. The wheel will have to come out again when I get the discs back from powdercoating - I want the centres coated black as they seem to look better for longer than if they were spraypainted.

01Thomas · « **Reply #51 on:** May 19, 2015, 02:23:28 PM »

I have posted a query in the General forum about the primary drive sprocket; in case you haven't seen it, it's here:
http://forums.sohc4.net/index.php/topic,147959.msg1685505.html#msg1685505
Any advice would be appreciated.

I've also refurbished the oil pump. It all seemed fine so I didn't replace the seal in the centre, just the two large o-rings inside the rotor endcaps. The rotors are the cleanest/least worn I have ever seen on a CB750 oil pump, with very little of the pitting that one usually sees on these. I have about six oil pumps here and these rotors are by far the best.

The upper and lower crankcases have been stripped and 'sodabraded' to remove the paint. At present they, the cylinder barrel, the head and the sump at the spraypainter being painted an aluminium colour similar to the original Honda colour.

SOHC4 Cafe Racer Fan · « **Reply #52 on:** May 19, 2015, 02:32:44 PM »

Quote from: 01Thomas on May 19, 2015, 02:23:28 PM

I have posted a query in the General forum about the primary drive sprocket; in case you haven't seen it, it's here:
http://forums.sohc4.net/index.php/topic,147959.msg1685505.html#msg1685505
Any advice would be appreciated.

I've also refurbished the oil pump. It all seemed fine so I didn't replace the seal in the centre, just the two large o-rings inside the rotor endcaps. The rotors are the cleanest/least worn I have ever seen on a CB750 oil pump, with very little of the pitting that one usually sees on these. I have about six oil pumps here and these rotors are by far the best.

The upper and lower crankcases have been stripped and 'sodabraded' to remove the paint. At present they, the cylinder barrel, the head and the sump at the spraypainter being painted an aluminium colour similar to the original Honda colour.

I've been trying to find a local sodablaster in SoCal

01Thomas · « **Reply #53 on:** May 19, 2015, 02:40:42 PM »

I'm a bit too far from SoCal to be of any help there.

01Thomas · « **Reply #54 on:** May 24, 2015, 11:37:32 AM »

Here's another question regarding the primary drive sprockets on the main shaft: did they change at all in the lifetime of the sohc750/4 ?

The reason I ask is that about 20 years ago I bought a NOS sprocket and I've never used it. It's still in good condition but it is not in a packet and there is no partnumber on. If they were the same throughout the years of manufacture I'll rather use the new one, refurbish the old one and keep that as a spare.

regards
Thomas

PS At more or less the same time I also purchased a NOS alternator cover which I also still have, safely tucked away.

Roach Carver · « **Reply #55 on:** May 24, 2015, 11:57:39 AM »

Subscribed!

jaguar · « **Reply #56 on:** May 25, 2015, 05:16:05 PM »

Love the mods to the center stand.
That is a great idea

straat-toe · « **Reply #57 on:** May 27, 2015, 06:19:32 AM »

Cool Story and project! Good luck.

01Thomas · « **Reply #58 on:** June 24, 2015, 02:08:45 PM »

Well I haven't been posting but the project hasn't been standing still.

The engine cases which I last got back from the painter have been put to use.
When I first built this motor all those years ago I had the conrods shotpeened, polished and then the whole crank assembly was balanced.
The 836cc Cruzinimage pistons with rings and gudgeon pins have now been installed onto the conrods, and they've been fitted into the bored out cylinders.

I have also fitted the Kibblewhite HD cylinder studs to the upper crankcase; I have installed the new Tsubaki camchain along with a new camchain tensioner into the upper crankcase half and I've installed the stock basegasket with new Viton o-rings.

01Thomas · « **Reply #59 on:** June 24, 2015, 02:14:13 PM »

Turning the upper crankcase over, I have installed new big-end bearing shells and new main bearing shells. Both measured out to require the Brown size and I got them from the local Honda dealer.
I've installed the new primary drive chains onto the crankshaft and then also the lower loop of the camchain.

01Thomas · « **Reply #60 on:** June 24, 2015, 02:24:38 PM »

The project has also suffered something of a setback: About 18 months ago I stripped the rear wheel. I had the rim cleaned up and chromed, I had the spokes and nipples galvanised and I had the hub polished. I then assembled the wheel loosely before passing it on to a mate who's good with trueing wheels. When I got it back i stored it in my garage and then did the same for my front wheel.

The upshot is that after standing in the garage for 18 months the rear wheel is rusting away merrily. and after standing in the garage for some 12 months the chrome on the front wheel is peeling of when you just look at it.

Needless to say I've stripped the wheels again and have taken them to be redone by the same crowd who messed up first time. It doesn't represent much of a cost but it does frustrate the hell out of me

SOHC4 Cafe Racer Fan · « **Reply #61 on:** June 24, 2015, 02:46:13 PM »

Quote from: 01Thomas on May 19, 2015, 02:08:06 PM

Busy...yes...

I also fitted the mainstand. My philosophy is that although this is a sports machine, I ride on the street not on the racetrack, and a mainstand is a nice thing to have, even if it weighs about a kilogram. This stand is heavily modified to make clearance for the Yoshimura-style 4-1 exhaust - these mods show up quite well in the photos!

I have also fitted the front wheel with it's mudguard and the refurbished brake callipers. The wheel will have to come out again when I get the discs back from powdercoating - I want the centres coated black as they seem to look better for longer than if they were spraypainted.

Nice centerstand mod. If the thing didn't weigh a half ton, it would be nice to have on a race bike as well, eliminating the need for a paddock stand.

01Thomas · « **Reply #62 on:** June 24, 2015, 02:48:20 PM »

Many years ago when Axl (The Satanic Mechanic) was still alive we had a decent correspondence going on, coincidentally at the exact time when he was having a set of replica Seeley Honda seats made - so I asked him to make me two while he was at it.
I've been lugging them around with me for the past 15 ?? years and obviously now is the time to put one of them to use. The seal that I've had on this bike is a bastardised (the dreaded PO...) and somewhat refurbished remnant of the original seat.

I have now fitted the new seat and I have cut-out the hole for the stock Honda brake & taillight and have provisionally fitted it to the bike.

01Thomas · « **Reply #63 on:** June 24, 2015, 02:54:57 PM »

This photo shows how I fitted the indicators to the old seat cowl: I drilled a hole for the indicator stub and then screwed it all together with large washers on the inside and the outside.
My question is: is this the best way to do it with the new seat? Is there a better way of mounting the original Honda indicators? How did Colin Seeley design it?

Scottly, I see your bike has something like the original seat: how are the rear indicators fitted to your bike?
[EDIT: Scottly, i'm mistaken. You don't seem to have a Seeley seat on the bike on your profile pic].
And while I'm asking questions about the seat: what's the preferred way to mount the numberplate to the eat cowl?

regards
Thomas

SOHC4 Cafe Racer Fan · « **Reply #64 on:** June 24, 2015, 04:21:57 PM »

Quote from: 01Thomas on June 24, 2015, 02:54:57 PM

This photo shows how I fitted the indicators to the old seat cowl: I drilled a hole for the indicator stub and then screwed it all together with large washers on the inside and the outside.
My question is: is this the best way to do it with the new seat? Is there a better way of mounting the original Honda indicators? How did Colin Seeley design it?

Scottly, I see your bike has something like the original seat: how are the rear indicators fitted to your bike?
[EDIT: Scottly, i'm mistaken. You don't seem to have a Seeley seat on the bike on your profile pic].
And while I'm asking questions about the seat: what's the preferred way to mount the numberplate to the eat cowl?

regards
Thomas

I'm not sure IF Seeley designed their kit to incorporate signals. The pictures of Seeley Hondas that I have seen do not have signals mounted -- only the brake and head lights.

Here are some pictures of Carpy's Seeley with Brit plates:

http://www.cb750cafe.com/blog/my-old-seeley-honda/

http://caferacersociety.blogspot.fr/2007/09/carpy-on-history-of-seeley-750.html

jaguar · « **Reply #65 on:** June 25, 2015, 05:18:54 AM »

That is one good looking seat!

01Thomas · « **Reply #66 on:** June 25, 2015, 10:59:38 AM »

Well today I started to assemble the crankcases. When they were together I fitted the ten crank main bearing bolts, tightened them finger tight and then just as a check I tried to turn the crank... which did a 270° of a revolution and then stopped with a clunk. I then tried to turn it backwards and again it went about three quarters of a turn and then stopped with another clunk.

I then stripped off the lower crankcase half again and now that the load is reduced the crank does a full revolution but at two points it makes a scraping sound.

So I have some investigating to do this weekend (get the tube of mechanic's blue out) but I suspect the crank counter weights are contacting the cylinder liners/sleeves. Quite why that should be I don't know because it was fine before I stripped the motor (the cylinders weren't resleeved) but it will be one of the things I'll look at.

When I rebuilt my Bimota I fitted a 1170cc Wiseco kit which needed the bores to be resleeved, and one of them was marginally too long and made contact with the crank counterweight.

scottly · « **Reply #67 on:** June 25, 2015, 08:50:37 PM »

Quote from: 01Thomas on June 24, 2015, 02:54:57 PM

Scottly, I see your bike has something like the original seat: how are the rear indicators fitted to your bike?
[EDIT: Scottly, i'm mistaken. You don't seem to have a Seeley seat on the bike on your profile pic].
And while I'm asking questions about the seat: what's the preferred way to mount the numberplate to the eat cowl?

regards
Thomas

My Seeley never had indicators installed. The seat in my avatar is the original that I modified decades ago. It's similar in shape to Jaguar's, but is fiber-glass instead of steel. These were the two-up seats, fitted with the "small" gas tanks, possibly only on the early kits?

01Thomas · « **Reply #68 on:** June 27, 2015, 01:25:52 PM »

OK thanks Scott. I've never seen the dual seat up close before. All three Seeley Hondas here in SA are single seat versions.

BTW - the clunking that I heard and felt in my engine turned out to be nothing more than the free loop of the camchain bunching up. Once I tensioned the chain with my hand the engine turned over smoothly. So today I fitted the partially assembled engine into the frame.

As far as the indicators are concerned have a book called "The Superbikes" by Mike Winfield and Laurie Caddell (Galley Press, 1981). It has a chapter of 2 pages on the Seeley Honda CB750 and that bike has indicators, the rear ones approximately where my ones where fitted to the old seat cowl. In fact that's probably what I was modelling them on when I first built the bike.
When I get my scanner going I'll put the whole article here somewhere.

jaguar · « **Reply #69 on:** June 30, 2015, 07:48:44 AM »

[/quote]
My Seeley never had indicators installed. The seat in my avatar is the original that I modified decades ago. It's similar in shape to Jaguar's, but is fiber-glass instead of steel. These were the two-up seats, fitted with the "small" gas tanks, possibly only on the early kits?
[/quote]

Mine is steel, but looks very much like your dual seat.
I have also assumed that I have the smaller tank too.

I talked to Colin and I think that our bikes might have been delivered together to the same person when new.
Small world.

Zunspec · « **Reply #70 on:** July 16, 2015, 05:33:50 AM »

Hello Thomas,

Here are a couple of photos on the rear number plate mounting on my bike. Basically a simple flat steel plate (although mine has crease in it, to be sorted). I can take it off and provide dimensions etc. if it will help.

Cheers Geoff

01Thomas · « **Reply #71 on:** July 17, 2015, 04:10:55 PM »

Thanks Geoff, that's a big help. I can estimate the width of the plate from the width of the recess in the seat cowl and make a suitable plate.

regards
Thomas

Zunspec · « **Reply #72 on:** July 17, 2015, 04:31:15 PM »

Hello Thomas,

I think it goes behind the tail light and as I need to take it off to straighten that crease I will take photos and also provide some dimensions. It will be the first part to be "sorted" on my bike

Cheers Geoff

01Thomas · « **Reply #73 on:** July 19, 2015, 11:03:19 AM »

Behind the tail light? OK thanks. That's more complicated but not really a problem.

Cheers
Thomas

Zunspec · « **Reply #74 on:** July 19, 2015, 12:55:51 PM »

A not very good photo, but you can see the hole cut out for the tail light holder. The upper mounting bolts, which screw into the tail light, are rubber isolated. There's another two plastic No. plate type bolts lower down, although they do not go through the actual No. plate. They may have been an owner mod to limit any flapping.

Cheers Geoff

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Author Topic: Seeley Honda CB750F - SH7-655F - - the rebuild starts (Read 14401 times)