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+--- Thread: Oversize gudgeon pins (/showthread.php?tid=1891)
RE: Oversize gudgeon pins - Zetomagneto - 23-10-2018
(23-10-2018, 07:37 AM)Ruairidh Dunford Wrote: Simon,
in your shoes, I would be looking to source another rod.
However if you do proceed as discussed above, remember you will need clamp type gudgeon pins.
At the moment we don’t know what rods Simon has, but yes obviously clamp type for clamp type rods but others have converted clamp type rods to fully floating by inserting an appropriate thickness of packing in the slot and boringe the hole.This was done to use The Honda pistons,we don’t need to do that now as Tony does the slipper pistons.
Simons question was where to get oversize pins, it has been answered.Simon can use 13mm pins, if he has clamp type rods he can grind,or have ground the clearance in the middle of the pin for the clamp bolt.Another rod was suggested early in the thread, clearly he does not want to do it that way.
RE: Oversize gudgeon pins - Ruairidh Dunford - 23-10-2018
If the rods are suitable for floating pins I personally would have new bushes made up for the little end eyes - I had to do this very recently to convert back to standard pistons from Honda ones.
RE: Oversize gudgeon pins - Zetomagneto - 23-10-2018
(23-10-2018, 08:21 AM)Ruairidh Dunford Wrote: If the rods are suitable for floating pins I personally would have new bushes made up for the little end eyes - I had to do this very recently to convert back to standard pistons from Honda ones.
Interesting, why didn’t you follow your own advice and just use another set of rods.It leaves them weak,You have to take out more material in order to bush them.
RE: Oversize gudgeon pins - Ruairidh Dunford - 23-10-2018
The rods were fitted with bushes to suit the 13mm floating pins of the Honda pistons.
We simply removed these bushes and made up new ones to suit the 1/2” standard sized floating pins.
There was no need to replace the Pheonix rods as the o/d of the bushes was identical and the little end unchanged from the way they were produced.
RE: Oversize gudgeon pins - "Slack Alice" Simon - 23-10-2018
I do like the way a simple question gets all sorts of subsequent information out into the open.
As one who is good at making things go, but not an engineer:
Why a left hand reamer instead of a normal one?
I don't suppose it is the same as running a normal one in reverse because you don't want an aggressive cut, more of a scrape.
Simon
RE: Oversize gudgeon pins - Zetomagneto - 23-10-2018
(23-10-2018, 10:40 AM)Ruairidh Dunford Wrote: The rods were fitted with bushes to suit the 13mm floating pins of the Honda pistons.
We simply removed these bushes and made up new ones to suit the 1/2” standard sized floating pins.
There was no need to replace the Pheonix rods as the o/d of the bushes was identical and the little end unchanged from the way they were produced.
Sorry Rory, thought you were talking about Nippy rods just goes to show, one needs all the info before making a comment.Just fine to rebush where there were bushes originally.
I would be interested in the Honda pins if unworn.
Best Wishes Gene
(23-10-2018, 11:17 AM)Slack Alice Wrote: I do like the way a simple question gets all sorts of subsequent information out into the open.LH fluted reamer pushes the swarf ahead, rather than pulling it back over what you have just reamed.
As one who is good at making things go, but not an engineer:
Why a left hand reamer instead of a normal one?
I don't suppose it is the same as running a normal one in reverse because you don't want an aggressive cut, more of a scrape.
Simon
Never turn a reamer backwards/ anti-clockwise
RE: Oversize gudgeon pins - Ruairidh Dunford - 23-10-2018
I will pass your details onto the owner so they can contact you, if they wish to sell them.
RE: Oversize gudgeon pins - Zetomagneto - 23-10-2018
(23-10-2018, 04:16 PM)Ruairidh Dunford Wrote: I will pass your details onto the owner so they can contact you, if they wish to sell them.
Thanks Rory
RE: Oversize gudgeon pins - "Slack Alice" Simon - 23-10-2018
Once again, thanks for the help.
Pins and reamer ordered.
Just for interest, what size are the pistons? I have seen Honda pistons mentioned in the Forum but never taken any notice, because that is "racing boys stuff" and I just do "standard stuff"!
Simon
RE: Oversize gudgeon pins - Zetomagneto - 23-10-2018
(23-10-2018, 06:32 PM)Slack Alice Wrote: Once again, thanks for the help.
Pins and reamer ordered.
Just for interest, what size are the pistons? I have seen Honda pistons mentioned in the Forum but never taken any notice, because that is "racing boys stuff" and I just do "standard stuff"!
Simon
Honda pistons although high quality were never ideal because the compression height is too short meaning that compromises were made, the top and bottom of the block was skimmed, top of crankcase skimmed, .010” off all 3 surfaces and often no block to crankcase gasket.
No need to go to all that trouble now as slipper piston are available from Tony Betts, these are good for road/ standard engines as well as racing.Available sizes 56 through to 57.75mm, fully floating or clamp type pins either type pin are .5” diameter.
What type rods do you have? Are you the Simon who has a Cambridge special?
Best Wishes Gene