Author Topic: Seeley Honda CB750F - SH7-655F - - the rebuild starts (Read 14505 times)

01Thomas · « **Reply #75 on:** August 13, 2015, 02:40:54 PM »

OK, I think it's time for my 6-monthly update... ha ha ha... As mentioned before, I have been making progress but just not posting it here.

Chassis-wise I have had all the indicator components rechromed and I'll be fitting them as seen on Geoff's bike - which is also more or less the way i had them before this rebuild - except that now they're going into a new seat.

I have also had to remanufacture the gearshift linkage (the external parts) because the threads on the adjustment rod were close to finished. so I just fitted new ball joints too.

01Thomas · « **Reply #76 on:** August 13, 2015, 02:50:39 PM »

As mentioned elsewhere in this thread I have also started to assemble the engine. I assembled it all up to the head gasket on the bench (but excluding the clutch, starter and gearchange mechanism) and then installed it in the frame.

scottly · « **Reply #77 on:** August 16, 2015, 09:18:10 PM »

Quote from: 01Thomas on August 13, 2015, 02:40:54 PM

I have also had to remanufacture the gearshift linkage (the external parts) because the threads on the adjustment rod were close to finished. so I just fitted new ball joints too.

Thomas, fit jam nuts on both ends of the rod, as the lack of them will allow slop and wear on the threads. Also, check that the rod ends have clearance to the levers if the rod is angled to the side. Spherical rod ends don't have much clearance when run at an angle, and may need a small diameter spacer fitted to allow clearance.

Retro Rocket · « **Reply #78 on:** August 16, 2015, 09:19:24 PM »

Hi Scott, I just realized that you have Kawasaki wheels on your Seeley...

Just bought a set myself..

scottly · « **Reply #79 on:** August 16, 2015, 09:21:53 PM »

Quote from: Retro Rocket on August 16, 2015, 09:19:24 PM

Hi Scott, I just realized that you have Kawasaki wheels on your Seeley... Just bought a set myself..

I did have a Kawi wheel on the front for a brief time.

Retro Rocket · « **Reply #80 on:** August 16, 2015, 09:32:06 PM »

Quote from: scottly on August 16, 2015, 09:21:53 PM

Quote from: Retro Rocket on August 16, 2015, 09:19:24 PM
Hi Scott, I just realized that you have Kawasaki wheels on your Seeley... Just bought a set myself..
I did have a Kawi wheel on the front for a brief time.

What was the rear..?, I just got a 2.15 front and a 2.5 rear, I'm thinking about getting the rear widened to 3.5..

scottly · « **Reply #81 on:** August 16, 2015, 09:47:20 PM »

Do you mean Kawasaki or Morris? Both my Morris wheels are 2.15. I still have the Kawi front, plus two different Kawi rear wheels that I can check the size on.
About 15 years ago, I was sitting in the local pub when a fellow approached me and asked if that was my Seeley parked outside. I was astonished that he knew what it was, and when asked he replied that he figured it was either a Seeley or a Rickman and took a guess. Turned out he used to race a top fuel Kawi, until he had one blow the cylinder head straight up off the motor.

At the time I met him, he was riding a much tamer Harley cruiser with a turbo.

Anyway, every time we crossed paths after that, he teased me about having Kawi wheels on the Seeley, even before the temporary wheel swap.

Retro Rocket · « **Reply #82 on:** August 16, 2015, 09:53:30 PM »

Quote from: scottly on August 16, 2015, 09:47:20 PM

Do you mean Kawasaki or Morris? Both my Morris wheels are 2.15. I still have the Kawi front, plus two different Kawi rear wheels that I can check the size on.
About 15 years ago, I was sitting in the local pub when a fellow approached me and asked if that was my Seeley parked outside. I was astonished that he knew what it was, and when asked he replied that he figured it was either a Seeley or a Rickman and took a guess. Turned out he used to race a top fuel Kawi, until he had one blow the cylinder head straight up off the motor. At the time I met him, he was riding a much tamer Harley cruiser with a turbo. Anyway, every time we crossed paths after that, he teased me about having Kawi wheels on the Seeley, even before the temporary wheel swap.

I'll reply in PM's, already spammed up the seeley thread...

scottly · « **Reply #83 on:** August 16, 2015, 10:03:26 PM »

Tommy might appreciate the Seeley part of my story, which wouldn't have come up if you hadn't asked about the wheels, Mick.

01Thomas · « **Reply #84 on:** August 17, 2015, 01:55:32 PM »

Quote from: scottly on August 16, 2015, 09:18:10 PM

Quote from: 01Thomas on August 13, 2015, 02:40:54 PM

I have also had to remanufacture the gearshift linkage (the external parts) because the threads on the adjustment rod were close to finished. so I just fitted new ball joints too.
Thomas, fit jam nuts on both ends of the rod, as the lack of them will allow slop and wear on the threads. Also, check that the rod ends have clearance to the levers if the rod is angled to the side. Spherical rod ends don't have much clearance when run at an angle, and may need a small diameter spacer fitted to allow clearance.

Yes thanks Scott, will do. People often ignore fretting wear but that is what destroys the threads on a linkage like this.
Oh and I also fitted a flatwasher between the rod end and the splined levers. And I used hex-headed s/s screws (instead of Allen screws) because the clearance to the gear-change case is minimal.

01Thomas · « **Reply #85 on:** August 17, 2015, 01:59:54 PM »

Everybody likes a photo of a cleaned up inlet port - here is mine, from my cyl #1

01Thomas · « **Reply #86 on:** August 17, 2015, 02:03:46 PM »

And here's a photo of the underside of my cylinder-head, waiting to be installed.

As you can see In my previous life, when I first built this engine I went nuts with a drill

01Thomas · « **Reply #87 on:** August 17, 2015, 02:12:52 PM »

I suspect that the Seeley frame didn't change much from the first K-bikes to the later F-types and this leads to the next photo of a hydraulic jack supporting the front of the engine.

It is possible to fit the head to the engine in the frame but it's not that easy because the exhaust studs weren't there when Colin Seeley first designed the frame. Those earlier engines used exhaust screws and not exhaust studs.
Anyway on my bike it's a lot easier to fit the head to the engine if one removes all the engine mountings except the lower rear one and then slowly and carefully tilts engine a bit down in front using the aforementioned hydraulic jack to control the motion.

Once the head is in place one can use the jack to raise the front of the engine again and to refit the rest of the engine mountings.

01Thomas · « **Reply #88 on:** August 17, 2015, 02:15:52 PM »

Oh and I do have one true-blue item of RC Engineering tuning kit: an R.C. Eng cam sprocket!

01Thomas · « **Reply #89 on:** August 17, 2015, 02:19:55 PM »

And here is the assembled head incorporating Hondaman's rocker enlarged oil hole mod and nix rockershaft hold-down screws

SOHC4 Cafe Racer Fan · « **Reply #90 on:** August 17, 2015, 02:29:47 PM »

Are the drilled holes only on the bottom fins of the head? I did not see the holes in the head in the picture of the engine with the top end assembled.

01Thomas · « **Reply #91 on:** August 17, 2015, 02:38:44 PM »

No, I only went nuts in the lowest of the fins. Maybe that's when sanity returned?

Quote from: CB750 Cafe Racer Fan on August 17, 2015, 02:29:47 PM

Are the drilled holes only on the bottom fins of the head? I did not see the holes in the head in the picture of the engine with the top end assembled.

Swoop · « **Reply #92 on:** August 18, 2015, 11:39:04 AM »

Quote from: 01Thomas on August 17, 2015, 02:12:52 PM

I suspect that the Seeley frame didn't change much from the first K-bikes to the later F-types and this leads to the next photo of a hydraulic jack supporting the front of the engine.

It is possible to fit the head to the engine in the frame but it's not that easy because the exhaust studs weren't there when Colin Seeley first designed the frame. Those earlier engines used exhaust screws and not exhaust studs.
Anyway on my bike it's a lot easier to fit the head to the engine if one removes all the engine mountings except the lower rear one and then slowly and carefully tilts engine a bit down in front using the aforementioned hydraulic jack to control the motion.

Once the head is in place one can use the jack to raise the front of the engine again and to refit the rest of the engine mountings.

I experienced the same issues with my early K frame, thinking it was due to the early design. I guess this is the case with all frames....I feel better now.
Thanks for all your shared info.
Steve

01Thomas · « **Reply #93 on:** August 23, 2015, 09:44:02 AM »

Hi
I've hit a snag with the gearbox output shaft, carrying the sprocket. I don't want to duplicate posts so I've asked a question in the SOHC/4 Bikes forum:
http://forums.sohc4.net/index.php/topic,150838.0.html

Any ideas will be greatly appreciated.

regards
Thomas

straat-toe · « **Reply #94 on:** August 25, 2015, 07:27:03 AM »

I'm Learning loads about the Seeley here Thomas.

Never knew much about them at all.

Great work.

01Thomas · « **Reply #95 on:** August 25, 2015, 02:10:48 PM »

If you've been following my transmission/drive sprocket issues here http://forums.sohc4.net/index.php/topic,150838.0.html you'll have seen that this problem has been resolved and the build slowly continues.

At this stage I'm waiting for the wheels to be re-rechromed, rebuilt and trued - not really a hold-up but it would mark an important point in the rebuild.

I've started cutting a half-moon shape out of the fibreglass seat pan to make way for the fuel tap. This is fitted to the very back of tank, slightly to the right of centre, and I want my gloved hand to be able to switch from main to reserve while I'm riding. Photos to come.

01Thomas · « **Reply #96 on:** August 25, 2015, 02:11:41 PM »

:-)

Quote from: straat-toe on August 25, 2015, 07:27:03 AM

I'm Learning loads about the Seeley here Thomas.

Never knew much about them at all.

Great work.

jaguar · « **Reply #97 on:** August 26, 2015, 11:57:36 AM »

Quote from: 01Thomas on August 17, 2015, 02:19:55 PM

And here is the assembled head incorporating Hondaman's rocker enlarged oil hole mod and nix rockershaft hold-down screws

Got a link to his write up on this modification?
Or info on it?

01Thomas · « **Reply #98 on:** August 26, 2015, 12:55:59 PM »

Hi Jaguar
I don't have a link but he discusses it extensively in his book and that's where I saw it. (Page VI A-21 in the paperback version).
It involves elongating the oil hole in the rocker so that the oil groove in the rocker shaft has access to more oil. The oil hole elongation is generally 1mm? It doesn't really weaken the rocker because the hole is lengthened into the countersink and metal removed is minimal.
And then remove the 5mm rocker-shaft screws so that the shaft is free to rotate.

regards
Thomas

jaguar · « **Reply #99 on:** August 26, 2015, 01:03:57 PM »

I still need to pick up that book.

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Author Topic: Seeley Honda CB750F - SH7-655F - - the rebuild starts (Read 14505 times)

Swoop