Author Topic: valves appearance  (Read 3220 times)

Offline eugenius

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Re: valves appearance
« Reply #45 on: 07.02. 2024 22:16 »
Thanks Limeyrob, I have removed the 4 valves guides and remeasured all more precisely the size of the guides is actually smaller 0.535inch (maybe I smoked something too strong..), so which bronze guides size should I take? Regards
Rome 56 A10

Offline bikerboy

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Re: valves appearance
« Reply #46 on: 19.02. 2024 11:47 »
Have you thought about having the exhaust seats changed to adapt to the latest ethanol fuel? It may not be a problem in your country but the fuel over here in the UK is now rubbish.

Just a thought but if you do heavy milage its worth doing


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Offline Swarfcut

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Re: valves appearance
« Reply #47 on: 19.02. 2024 20:49 »
 Alloy head will already have seat inserts. Any problems running unmodified alloy heads on E5 or E10 here in the UK?

 Swarfy.

Offline eugenius

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Re: valves appearance
« Reply #48 on: 19.02. 2024 21:34 »
Hi bikeboy, thanks for the suggestion but I do not use my A10 that much. I am just waiting the newly ordered valve guides (SRM colsibro) to reassemble the engine and see if I can eventually enjoy a bit this bike on springer..
Rome 56 A10

Online sean

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Re: valves appearance
« Reply #49 on: 19.02. 2024 22:58 »
Have you thought about having the exhaust seats changed to adapt to the latest ethanol fuel? It may not be a problem in your country but the fuel over here in the UK is now rubbish.

Just a thought but if you do heavy milage its worth doing

We have E10 here in Canada and talking about E 15 havent had any problems yet but I agree ethanol fuel is bad for carb engines.

Offline bikerboy

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Re: valves appearance
« Reply #50 on: 20.04. 2024 22:09 »
Any problems running unmodified alloy heads on E5 or E10 here in the UK?
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The fuel in the uk is awful it takes a lot of messing around with the timing etc at times just to stop the pinking


BSA A10 x 4
BSA A65 Lightning
Triumph T150v
Tribsa (A10 frame 750 Bonnie motor)

Online sean

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Re: valves appearance
« Reply #51 on: 21.04. 2024 00:20 »
Any problems running unmodified alloy heads on E5 or E10 here in the UK?
--------------------------------------------------------------------

The fuel in the uk is awful it takes a lot of messing around with the timing etc at times just to stop the pinking
...I put 7 to 1s in my super rocket when I rebuilt the motor no problems with low compression and crap gas and easier to start for me at 76

Online Klaus

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Re: valves appearance
« Reply #52 on: 21.04. 2024 10:23 »
The valveseats are not the problem, the y could run without lead and with ethanolfuel.
Running on hight compression is the problem. Compression ratios 9to1 and more in conjunktionn with Megacycle cams is a pain with this bad fuels. Pinking under load, engine running hot and lost of power. Runing fairly only with premium fuels.

cheers Klaus


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Online limeyrob

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Re: valves appearance
« Reply #53 on: 21.04. 2024 10:33 »
Eugenius, apologies for not replying. I've bought the oversize guide from SRM and I'm having them turned to fit the head.  They come undersize on the bore so they have to be honed out too.  Its been at the shop for 3 weeks now so I can't tell you how its worked out yet.
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Offline eugenius

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Re: valves appearance
« Reply #54 on: 21.04. 2024 20:24 »
Thanks limeyrob and thanks all for replying. I also made the same with my guides SRM colsibro oversized adapted to be mounted. Resolved  small issues with carburator leaks, once reassembled the engine with new valves, springs and guides it seems to run quite fine, it starts on the first attempt and keep nicely the minimum. When riding for a small round near my homeplace (I still have no insurance) however carburation seems not perfect and I suspect I will not be really able to adjust it. Yet I am learning a lot thanks to you all. We will see... Ciao
Rome 56 A10