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Discussion Starter #1
hi all i have a spare oem barrel thats been ported and have noticed it looks like there is a hair line crack right in the middle of the exhaust bridge just in the iron sleeve not the alli casting,there has been some material taken out of the bridge in the porting.if i get it resleeved would it be ok to leave the bridge of the new sleeve standard dimensions or not as thin as before thou this would not match the bridge in the casting as that would be thinner ,im thinking that its cracked cos of the lack of material in the bridge. cheers paul
 

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Discussion Starter #3
hi yes i have seen that done before i would be a little concerned about piston /ring wear! could i possibly get away with the crack in leaving it!
 

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hi yes i have seen that done before i would be a little concerned about piston /ring wear! could i possibly get away with the crack in leaving it!
We re-sleeve at BDT all the time, based on experience:

You can bore out old OEM sleeve, re-sleeve, match porting, bore and hone....cost is rather high to do it correctly, and since it will be a pressed on sleeve vs the OEM 'Trapped' Cast Sleeve....reliability of the OEM cylinder is diminished.

IMO best to find a good used OEM cylinder.

Carlos
 

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Discussion Starter #5
on the resleeving that you do have you had many problems carlos.what is your thoughts on removing bridge cheers paul.
 

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on the resleeving that you do have you had many problems carlos.what is your thoughts on removing bridge cheers paul.
No, not problems per say.

Just consider as I stated Honda Cast the steel sleeves in place, they have undercuts on the sleeve to capture the casting material and lock the sleeve in one spot. OEM sleeves cannot move, never move, they are the most solid and reliable. Pressed in sleeves, no matter whose cylinder, always tend to want to move, up or down....certainly not as reliable.

Plus; Heat transfer is always more efficient on an OEM cylinder; cast in sleeves are basically one with the Aluminum Cast cylinder, and transfer of heat is most efficient vs pressed in sleeves.

Don't remove the bridge on an OEM cylinder as the exhaust port is already wide, the bridge is their to support the piston. On aftermarket cylinders without a bridge, that is a different story since the exhaust port width Percentage relative to the bore is smaller than on a OEM cylinder.

Carlos
 

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Discussion Starter #7
ok thanks dont think ill bother with resleeving it then.ell i finally got my engine back together after machining the head etc as i posted before and now able to use the metal gaskets and not the fibre ones which leak,i didnt quite get the float height right as it was coming over filling i seemed to struggle with that task but i just bent it down a tad now ok,and get to ride it tomorrow so we shall see fingers crossed cheers for your advice.
 

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ok thanks dont think ill bother with resleeving it then.ell i finally got my engine back together after machining the head etc as i posted before and now able to use the metal gaskets and not the fibre ones which leak,i didnt quite get the float height right as it was coming over filling i seemed to struggle with that task but i just bent it down a tad now ok,and get to ride it tomorrow so we shall see fingers crossed cheers for your advice.
I always try to reason with folks not to re-sleeve an OEM cylinder unless absolutely necessary....!

Carlos
 
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