Author Topic: 750 K2 Strip & Rebuild - help please  (Read 20969 times)

Offline taysidedragon

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Re: 750 K2 Strip & Rebuild - help please
« Reply #60 on: March 31, 2022, 04:14:55 PM »
You just use a center punch at 3 points  ;)

Are the balls a slight interference fit, so they seal when tapped in to place. The peening just stops them being vibrated or pushed out?
Gareth

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Offline Trigger

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Re: 750 K2 Strip & Rebuild - help please
« Reply #61 on: March 31, 2022, 04:31:27 PM »
You just use a center punch at 3 points  ;)

Are the balls a slight interference fit, so they seal when tapped in to place. The peening just stops them being vibrated or pushed out?

Tell me something i don't know, and i don't want to know what you had for breakfast  ;D ;D ;D
Once out it, is always good practice to replace them with grub screws and do not run the tap all the way though, only to the seating ledge  ;)

Offline Lobo

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Re: 750 K2 Strip & Rebuild - help please
« Reply #62 on: March 31, 2022, 09:38:51 PM »
…Nige, page #2 of this thread has a pic of the 3 punch marks. Patently done on a Monday morning after a heavy weekend on the saki….

Offline K2-K6

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Re: 750 K2 Strip & Rebuild - help please
« Reply #63 on: March 31, 2022, 10:00:30 PM »
Yes simon  I saw that and thought it was perhaps done later.  As you say maybe a Monday morning after heavy weekend.

It's more me with an aversion to stress raisers I suppose. Original background training during which if we were just paranoid about potential stress point,  then could be considered a bit of a lightweight in engineering terms  ;D

Point holes like that, thread peaks in stressed structures, no radius in tight machined corners all give the hee-b-gee-bees in stress terms.

Guess as a production item Honda specified the crank with plenty of meat on it to make it reliable. 

I've seen them closed in the way I describe, but can't immediately remember which crank it was.

Offline Lobo

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Re: 750 K2 Strip & Rebuild - help please
« Reply #64 on: April 01, 2022, 11:53:30 PM »
Yup, stress / fatigue in engineering more and more to the fore. My bil been very involved with live data vibration monitoring in helicopters - big business now. You have to wonder how the early Comets made it through to production - surely someone might have observed, “er, that radius looks a little tight given the fuselage will be pumped up & down like a balloon over its life….”  An interesting story that one.

I digress. Ok, a bit nerdy this one, my engine refurb has morphed into the whole bloody bike. Anyways, the Clutch and brake levers. Was the clear plastic covering intended to be taken off in the pdi. And if not, why is it there? Was it on both levers? Notably the DSS / Yamiya OEM offerings don’t appear to incorporate it.  (I ask because I intend to trial clear heat-shrink over the levers. My mint sandcast, which has been my go-to, has it only on one lever…. it seems I may have to return it 😂)

Ta.
« Last Edit: April 01, 2022, 11:57:15 PM by Lobo »

Offline taysidedragon

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Re: 750 K2 Strip & Rebuild - help please
« Reply #65 on: April 02, 2022, 01:08:15 AM »
Yup, stress / fatigue in engineering more and more to the fore. My bil been very involved with live data vibration monitoring in helicopters - big business now. You have to wonder how the early Comets made it through to production - surely someone might have observed, “er, that radius looks a little tight given the fuselage will be pumped up & down like a balloon over its life….”  An interesting story that one.

I digress. Ok, a bit nerdy this one, my engine refurb has morphed into the whole bloody bike. Anyways, the Clutch and brake levers. Was the clear plastic covering intended to be taken off in the pdi. And if not, why is it there? Was it on both levers? Notably the DSS / Yamiya OEM offerings don’t appear to incorporate it.  (I ask because I intend to trial clear heat-shrink over the levers. My mint sandcast, which has been my go-to, has it only on one lever…. it seems I may have to return it 😂)

Ta.

The Comet story is an interesting one. Being the first jet airliner in service and pressurised, flying at higher speeds and altitudes, it met with different problems never encountered before.
Unfortunately,  they learnt the hard way that square windows and metal fatigue don't work. The redesigned Comet had oval windows.
The test tank they used at Farnborough to discover the problem was still there on the airfield well into the Eighties,  I got a guided tour of it in the Seventies when my uncle worked there, it's maybe still there?
Gareth

1977 CB400F
1965 T100SS

Offline K2-K6

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Re: 750 K2 Strip & Rebuild - help please
« Reply #66 on: April 02, 2022, 10:25:59 AM »
The lever's coating appeared to have been dipped originally (from memory) as the pivot end looked like a thick paint that had dried in a tapered type ending.

Most bikes appeared to have it left on going to customer.

There was a coating we used at Farnborough years ago, called Vi-cote and seemed like a spray on  clear pvc, but can't trace anything of it now. Perhaps safety has done for it as it was in aerosol can to spray with.

Found this https://starscenic.net/ronan-vinyl-cote-uv-clear.html and wondering if it's anything like that product. 

Offline AshimotoK0

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Re: 750 K2 Strip & Rebuild - help please
« Reply #67 on: April 02, 2022, 10:37:38 AM »
The lever's coating appeared to have been dipped originally (from memory) as the pivot end looked like a thick paint that had dried in a tapered type ending.

Most bikes appeared to have it left on going to customer.

There was a coating we used at Farnborough years ago, called Vi-cote and seemed like a spray on  clear pvc, but can't trace anything of it now. Perhaps safety has done for it as it was in aerosol can to spray with.

Found this https://starscenic.net/ronan-vinyl-cote-uv-clear.html and wondering if it's anything like that product.

I used some ultra clear  heatshrink .. special stuff from RS Components. You chop a bit off and slot it onto the lever and then put in a pre-heated oven at 160 deg C (fan)  for a couple of minutes. Agreed original was probably a dip coat. Send some of this to a few people I rate for doing top restos and they thought it was a good solution. Will dig out the RS partno. Ordinary cheapo clear heatshink give a poor result.

https://uk.rs-online.com/web/p/heat-shrink-tubing/7004462


« Last Edit: April 02, 2022, 11:25:49 AM by AshimotoK0 »
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Offline Lobo

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Re: 750 K2 Strip & Rebuild - help please
« Reply #68 on: April 02, 2022, 12:48:02 PM »
…thanks gents.
Did try a ‘standard’ heat shrink today - not esp impressed. Will soldier on - thanks Ash for the link.

Still unsure what the purpose was…

Offline K2-K6

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Re: 750 K2 Strip & Rebuild - help please
« Reply #69 on: April 02, 2022, 01:51:11 PM »
Purpose, speculative that it's a relatively low cost way of giving protection to a high wear surface. Most polished surface (that from operation) leaves the alloy easily attacked by road salt, making a poor appearance over time.

Later type with black anodized finish (eatly 80s) appear to do the same thing, still get very polished in use but don't seem to succumb to corrosion. 

Presumably the original plastic coat was to preserve how the bike aged at reasonable cost in manufacturing.

Offline Trigger

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Re: 750 K2 Strip & Rebuild - help please
« Reply #70 on: April 02, 2022, 02:02:58 PM »
…thanks gents.
Did try a ‘standard’ heat shrink today - not esp impressed. Will soldier on - thanks Ash for the link.

Still unsure what the purpose was…

That wrap is tooo short. Here is a picture of an original.

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Offline Oddjob

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Re: 750 K2 Strip & Rebuild - help please
« Reply #71 on: April 02, 2022, 02:06:13 PM »
Never thought of why they put it on before but could be for grip, alloy can be slippery and maybe the plastic is grippier.

Saying that I removed mine and had the levers chromed, can't say I noticed any difference.
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Offline Lobo

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Re: 750 K2 Strip & Rebuild - help please
« Reply #72 on: April 02, 2022, 10:20:32 PM »
Thanks Trig. Little secret - all I had in my electrical box was 80mm of clear! (Trial run) But the measurement appreciated.
I’d have to say it doesn’t look dipped?

Simon
« Last Edit: April 02, 2022, 10:22:32 PM by Lobo »

Offline Trigger

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Re: 750 K2 Strip & Rebuild - help please
« Reply #73 on: April 02, 2022, 11:03:33 PM »
Thanks Trig. Little secret - all I had in my electrical box was 80mm of clear! (Trial run) But the measurement appreciated.
I’d have to say it doesn’t look dipped?

Simon

Yes, the original was dipped to get the cover on and then dipped again for the plastic ball cover  ;)

Offline Oddjob

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Re: 750 K2 Strip & Rebuild - help please
« Reply #74 on: April 03, 2022, 02:53:16 AM »
Ball cover is not dipped, it’s available as a spare, I fitted them to my chromed levers to make them look original.
Kids in a the back seat cause accidents.
Accidents in the back seat cause kids.

 

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