Author Topic: CB250RS Rebuild Progress  (Read 6354 times)

Offline MarkCR750

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Re: CB250RS Rebuild Progress
« Reply #30 on: December 02, 2017, 07:26:27 PM »
Look very nice, have fun getting the tyre fitting “soap” off!
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Offline AshimotoK0

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Re: CB250RS Rebuild Progress
« Reply #31 on: December 03, 2017, 01:56:50 AM »
I think the rebuild was in CMM and possibly the last resto that Rod Gibson did before he sadly passed away .... I may have a couple of copies with part of the rebuild in Dave. I will look over the w/end.

I don't have that engine strip copy  to scan Dave but you can download it here...think this is bottom end though

https://magazinesubscriptionsdigital.zinio.com/browse/issues/index.jsp;jsessionid=ABDC36CB6B47EECEEDE18446756B7E99.prd-main-news3?skuId=416161189&prnt=&categoryId=cat1960016
« Last Edit: December 03, 2017, 02:20:28 AM by AshimotoK0 »
“Alright friends, you have seen the heavy groups, now you will see morning maniac music. Believe me, yeah. It’s a new dawn.” Grace Slick, Woodstock '69 .. In the year of the Sandcast.

Offline AshimotoK0

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Re: CB250RS Rebuild Progress
« Reply #32 on: December 03, 2017, 11:53:47 AM »
Just found the CMM issue you need Dave I will scan it and post ...Thesame issue also had a very mistake ridden short section on my 400/4 by Mark williams of BIKE fame !
“Alright friends, you have seen the heavy groups, now you will see morning maniac music. Believe me, yeah. It’s a new dawn.” Grace Slick, Woodstock '69 .. In the year of the Sandcast.

Offline AshimotoK0

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Re: CB250RS Rebuild Progress
« Reply #33 on: December 03, 2017, 05:41:15 PM »
Here you go Dave ..I found both articles on the engine strip,scanned & PDF'd  :). Give it a short time though as it's a big file and taking a while to upload.

https://www.dropbox.com/s/318cabahyog0q9g/CB250RS_Strip_CMM_2011.pdf?dl=0
“Alright friends, you have seen the heavy groups, now you will see morning maniac music. Believe me, yeah. It’s a new dawn.” Grace Slick, Woodstock '69 .. In the year of the Sandcast.

Offline Laverda120

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Re: CB250RS Rebuild Progress
« Reply #34 on: December 03, 2017, 09:04:28 PM »
Wow, fantastic, thanks a million Ash. I was going to start the reassembly today but been too busy! I'll be out in the garage tomorrow on my day off and after reading these articles first :).

Offline HWG27

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Re: CB250RS Rebuild Progress
« Reply #35 on: December 04, 2017, 07:27:30 PM »
That's a good article. Didn't appear to have any particular problems with those rocker arm pins.
Here's the status of mine.
After dremmelling a grove [ Guests cannot view attachments ]
After tig attachment has broken off [ Guests cannot view attachments ]
After one last desperate wrench with the mole grips. [ Guests cannot view attachments ] .

Last chance saloon with the drill next.

Offline HWG27

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Re: CB250RS Rebuild Progress
« Reply #36 on: December 04, 2017, 07:47:02 PM »
I'm halfway through my wheels. Rear has been respoked (stainless) and the front will be going to hagons within the next week. It's not a nuts and bolts restoration so I've made my wheels nice and shiney.  8)
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I did have roadriders fitted but have dumped these, mainly because they were oversize. My own fault. I've got some soft heidenau's to go on.

Also I have fitted a twin pot caliper and larger disc, which possibly came from a 750 but could've been from pretty much anything.

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Offline Laverda120

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Re: CB250RS Rebuild Progress
« Reply #37 on: December 04, 2017, 08:05:16 PM »
Looking good Huw. Those pins are a pain especially when you reach the point of no return and they have to come out.
I think you may go the route I took with burning them out.

Offline Laverda120

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Re: CB250RS Rebuild Progress
« Reply #38 on: December 04, 2017, 09:30:26 PM »
Some good progress today, I began the engine rebuild this afternoon.  All going well so far with no mishaps. I bought a new balance chain after checking the old one and found it had stretched by over 20% despite only having 14k on the engine. The  original Honda chains (DID) are no longer obtainable but having spoken to Andy the chain man he measured it and advised it's actually a Go-kart drive chain, £12 for a racing spec DID chain compared to £280 for a genuine poorer quality item on e-bay!
Next job is to join the cases and fit the ancillaries before moving on to the top end next weekend.

Offline AshimotoK0

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Re: CB250RS Rebuild Progress
« Reply #39 on: December 04, 2017, 09:34:59 PM »
My  wife posted your  NOS rocker today Dave  :)
“Alright friends, you have seen the heavy groups, now you will see morning maniac music. Believe me, yeah. It’s a new dawn.” Grace Slick, Woodstock '69 .. In the year of the Sandcast.

Offline Laverda120

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Re: CB250RS Rebuild Progress
« Reply #40 on: December 04, 2017, 10:10:20 PM »
Thanks Ash. I bet it arrives quicker then the parts I ordered from CSMNL over a week ago and I'm still waiting for!

Offline Laverda120

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Re: CB250RS Rebuild Progress
« Reply #41 on: December 04, 2017, 10:15:02 PM »
Huw, I've just looked in close up at your rocker pads, they look OK, do you need to take them out?
I bought some special 500c heat proof adhesive at Kempton on Saturday, I'll need to glue my new pins in as although they will still be a tight fit they won't be a tight as before the old ones were spark eroded out.

Offline HWG27

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Re: CB250RS Rebuild Progress
« Reply #42 on: December 05, 2017, 03:39:47 PM »
No I probably didn't or don't need to take them out. Just that while I'm cleaning/painting everything it seemed worthwhile doing that. Would rather replace them now.  I certainly would've gone for a new balancer chain if I'd realised there were ready made replacements available, especially at that price. I've got bottom end pretty much together now though and reluctant to split cases again for this.

Offline Nurse Julie

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Re: CB250RS Rebuild Progress
« Reply #43 on: December 05, 2017, 03:48:15 PM »
Thanks Ash. I bet it arrives quicker then the parts I ordered from CSMNL over a week ago and I'm still waiting for!
I put in a big parts order with CMSNL on 11th October. All items were in stock but then they discovered 1 of the items wasn't in stock ( computer error they say !!!). Still waiting, estimated dispatch 12th December but, not guaranteed yet......2 bloody months!!!
Im a Nurse, trust me, this won't hurt.....much !!!

LINK TO MY CB400/4 ENGINE STRIP / ASSESSMENT AND REBUILD...NOW COMPLETE
http://www.sohc.co.uk/index.php/topic,14049.msg112691/topicseen.html#new

Offline Laverda120

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Re: CB250RS Rebuild Progress
« Reply #44 on: December 31, 2017, 03:37:37 PM »
Whilst I await the removal of the locking dowel from the rocker cover to enable me to complete the engine reassembly I turned my attention to rebuilding the carb. At least this is one completed job. I'll start on reassembly of the frame and forks tomorrow.