Author Topic: engine improvements  (Read 1863 times)

Online Klaus

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engine improvements
« on: 07.07. 2015 13:32 »
hello,
as l already announced here the first advice to get a more durable enginge for less wear.
It is fakt, that all moving parts (not turning) be lightend as can be.
Easy and keen are pushrods conversions.

You have fit original pushrods?
Ok this is second best. If you are cruising at max.4000 revs they are ok.

Someone recomment you SRM hight strength (strange) pushrods?
This will be the worst case......sorry to tell you

You ask why?
Now here the fakts.

I have scaled allways two pushrods long and short one.
Genuine ones are 83 gramms

The SRM ones are 133gramms
that means SRM pusrods are approx 62.5 % heavier

In conjunction with the low tension valvesprings it will be a disaster for cam and followers.
You all know the signs of exchange aggrement because they can't follow each other at higher revs.

Solution are alloy pushrods  from VW beatle, they can be used, often sale at ebay with a big deal for you.
Shortend to the righ length thy scale only 65gramms


Klaus


If you think, everything is under control, you are not fast enought.

Offline edboy

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Re: engine improvements
« Reply #1 on: 07.07. 2015 18:08 »
thanks for your information klaus. cam and follower wear is too great on my bsa and i would like to lighten the valve gear and believe the bsa standard valve springs are too heavy and non progressive. what are the low tension valve springs you are using ? who makes them?

Online Klaus

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Re: engine improvements
« Reply #2 on: 07.07. 2015 18:58 »
thanks for your information klaus. cam and follower wear is too great on my bsa and i would like to lighten the valve gear and believe the bsa standard valve springs are too heavy and non progressive. what are the low tension valve springs you are using ? who makes them?

hi edboy,
there will be a misunderstanding. standard valve springs are to low in tension.
A 357 cam at hight lift give a pressure about 65 kg to the standart springs at closed valves 35 kg.
I prefer 85 kg at highest lift, this is a good number for the valve pressure, otherwise the cam give the followers too much accelleration and they lift up. Pumping off the top of the cam and causes the usual signs of wear.
I shifting wrong gear and the result you seen at the pictures.

Tell you more about next week, when l left  the hospital with the pined collar bone.

cheers Klaus


If you think, everything is under control, you are not fast enought.

Online RichardL

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Re: engine improvements
« Reply #3 on: 07.07. 2015 19:33 »
So, you're saying what happened to the engine is a bad thing?  ;)
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020. This year it's a solo or pillion ride in dapper attire. Watch website at https://www.gentlemansride.com for details.


Offline worntorn

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Re: engine improvements
« Reply #4 on: 08.07. 2015 01:55 »
This company supplied  made to order hollow alloy pushrods for my Vincent Special.
The cost was very low and their pushrods are used in race engines all over the US.
Glen

http://www.pushrods.net/

Online muskrat

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Re: engine improvements
« Reply #5 on: 08.07. 2015 09:39 »
I have been using solid duralium push rods for years. Polished ends are a must to reduce wear.
Reduced weight of pushrods, rockerarms and valve keepers reduce the risk of valve bounce and float. My A7SS regularly saw 7500rpm on the track.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline edboy

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Re: engine improvements
« Reply #6 on: 09.07. 2015 21:33 »
the problem with the dural ones i once used in a norton was that the alloy turned out to be like cheese and they wore out like mad until they jumped out of the socket. volkswagon pushrods sound interesting as such a manufacturer would hopefully use adequate alloys that stand a little abuse.

Offline Sasel

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Re: engine improvements
« Reply #7 on: 11.08. 2015 21:07 »
Hi klaus,

All the best to your bones from Hamburg.

christian

Online Klaus

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Re: engine improvements
« Reply #8 on: 30.11. 2015 15:17 »
I gues it is time to make an update with the rockers.

Geting another engine with unmachined rockers, having a chance to take pictures befor and after.

Usefull item is a hexagon pin with a 5/16 BSC thead fixing the rocker in a milling maschine.

Best to explain is a look at the pictures.

The rockers don' t need to be polished. It is better the pairs have the same hight and being lightend.

cheers Klaus


If you think, everything is under control, you are not fast enought.

Online RichardL

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Re: engine improvements
« Reply #9 on: 30.11. 2015 16:43 »
Klaus,

First, this is very interesting. Second, due to limited experience, I am in no position to second-guess your machining choices, so I ask for the fun of it: Why a hex pin in a 4-jaw chuck?

Richard L.
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020. This year it's a solo or pillion ride in dapper attire. Watch website at https://www.gentlemansride.com for details.


Online Klaus

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Re: engine improvements
« Reply #10 on: 30.11. 2015 18:09 »
hi Richard

 *whistle*  l was to lacy to fit a 3-jaw chuck for the quater of an hour work on the mill. *roll*


cheers Klaus


If you think, everything is under control, you are not fast enought.

Online Klaus

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Re: engine improvements
« Reply #11 on: 29.03. 2019 08:12 »
hello,
as l already announced here the first advice to get a more durable enginge for less wear.
It is fakt, that all moving parts (not turning) be lightend as can be.
Easy and keen are pushrods conversions.

You have fit original pushrods?
Ok this is second best. If you are cruising at max.4000 revs they are ok.

Someone recomment you SRM hight strength (strange) pushrods?
This will be the worst case......sorry to tell you

You ask why?
Now here the fakts.

I have scaled allways two pushrods long and short one.
Genuine ones are 83 gramms

The SRM ones are 133gramms
that means SRM pusrods are approx 62.5 % heavier

In conjunction with the low tension valvesprings it will be a disaster for cam and followers.
You all know the signs of exchange aggrement because they can't follow each other at higher revs.

Solution are alloy pushrods  from VW beatle, they can be used, often sale at ebay with a big deal for you.
Shortend to the righ length thy scale only 65gramms


Klaus

Hi Klaus and All
I have fitted several sets of SRM pushrods and have not had any bad experiences

John

Hj John,

my first twin engine overhaul was made from SRM with a rollerbearing convertion. Its only last 10 tousand kilometres, (one year) one piston broke in line with the guedonpin, cam and folowers worn out, and I changed monthly the rockerbox seals, they are rubbed off.


cheers Klaus


If you think, everything is under control, you are not fast enought.

Online Sav

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Re: engine improvements
« Reply #12 on: 29.03. 2019 09:44 »
I had ally pushrods collapse in my A10SR left hand pot on a VMCC demonstration parade on Manxland (was tootling along a bit  *smile* )

They bent slightly and the middle wore against the pushrod tube side until the inevitable happened. Shipped steel ones out there to get going, but have had the SRM ones in there for the last eight years without problem.
1961 A10SR, spent a fortune at SRM
1961 A7SS, finally the right green
2011 New addition 1937 Empire Star, twin port, high pipes. Turned out to be the most unreliable bike I have handled.
2017 finally found the liner/barrel were flexing and causing all the overheating/nipping up. Early B33 barrel fitted and it's reliable at last!

Online Rex

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Re: engine improvements
« Reply #13 on: 29.03. 2019 09:59 »
I always mount hex's in a four-jaw chuck too. I like the accuracy compared to a three-jaw.

Online berger

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Re: engine improvements
« Reply #14 on: 29.03. 2019 11:50 »
I like it Klaus, it has given me food for thought with the future engine build. MUSKY you little wheelie  high revving geezer what did you do with your rockers. as in the prisoner a 1960's epic TV series the new number 2 says - WE WANT IMFORMATION! well I do please *smile*