Author Topic: Dowels or no?  (Read 806 times)

Offline Dellortoman

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Re: Dowels or no?
« Reply #15 on: August 09, 2018, 04:15 »
The Zane heads will only work if you manage to extract the heat faster/more efficiently, no matter what type of bearings you install. 

What's the fix for that problem? Greater oil flow perhaps?
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Offline Ventodue

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Re: Dowels or no?
« Reply #16 on: August 09, 2018, 08:20 »
What's the fix for that problem? Greater oil flow perhaps?

Ride faster - more air flow, you see ...  :D  :P

Offline Alexb83

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Re: Dowels or no?
« Reply #17 on: August 09, 2018, 12:55 »
Thank you all as always for your constructive comments and advice.

The bike has recently done an 1100 mile round trip including very hard riding, and had no compliants (aside from a little rattle at the top end after cold starts that has me concerned and thinking this check is now overdue)

We'll see what I find when I get it open, although now I am thinking I should resolve the 'dowel issue' before I start checking clearances, rather than after.

If I just assume that it's going to be a complete cams out/replace the dowels/renew cam chain (can't hurt?)/measure and re-shim as required job, is it going to make my life simpler? Would refreshing the bearings as a precaution be advisable if they have not been positioned with the dowels previously?

I don't want to measure clearances, potentially re-shim, then alter the cam position and end up having to re-measure for a fortnight as Piet suggests.
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Offline sfcpiet

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Re: Dowels or no?
« Reply #18 on: August 09, 2018, 20:13 »
What's the fix for that problem? Greater oil flow perhaps?

The factory tried that with a pump about 4 times the flow volume as the original Formula/600 pump.  Even added an oil channel between the exhaust valve seats and a pair of monstrous coolers and fans, heads still collapsed under the exhaust cam.  Just too much heat being generated, too much power expected from an air-cooled twin.  Reckon if the factory had put their ceiling at 60-65hp, all could have been good.

piet
180s feel quick, 120s are...      If it ain't broke, fix it till it is.

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Offline redax5

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Re: Dowels or no?
« Reply #19 on: August 09, 2018, 20:45 »
What's the fix for that problem? Greater oil flow perhaps?

ceramic coatings would alleviate a lot of the heat issue and is cheap as

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Offline Davo

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Re: Dowels or no?
« Reply #20 on: August 10, 2018, 02:10 »
ceramic coatings would alleviate a lot of the heat issue and is cheap as

Not buying one is even cheaper.
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Offline CLEMTOG

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Re: Dowels or no?
« Reply #21 on: August 10, 2018, 09:48 »
ceramic coatings are cheap?
I got a quote for the Old Duffers 1200 anni exhaust, (a new MC item last year and now green not black) and it was 600GBP.
and Nick you are still a lanky old bald headed legal eagle!
CLEM

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Offline Grant

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Re: Dowels or no?
« Reply #22 on: August 10, 2018, 10:26 »
I think ceramic external coatings such as exhausts may be a bit different to inside-engine applications.
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Offline redax5

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Re: Dowels or no?
« Reply #23 on: August 10, 2018, 16:09 »
ceramic coatings are cheap?
I got a quote for the Old Duffers 1200 anni exhaust, (a new MC item last year and now green not black) and it was 600GBP.
and Nick you are still a lanky old bald headed legal eagle!
CLEM

$270 AUD for 3 x combustion chambers, exhaust ports, exhaust valves, add another $90 for pistons ceramic crowns and dry film skirts
best money I have ever spent

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near Brisbane, Australia

Offline Andy

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Re: Dowels or no?
« Reply #24 on: August 10, 2018, 22:51 »
I looked at shiny ceramic coating as an alternative to rechroming my tatty looking headers. Quoted NZ$200. Not bad I thought, until they told me the additional cost of stripping the remaining chrome... $300!

They're painted black now, while I save up for a full set from Malcolm...  ::)
'84 RGS and loving it
(might have to sell the old honda...)