Compatible Cam Chain Tensioners

[JaMax]

I'm looking to do the mod on my cam chain tensioner but would like to pick up a used one so I don't have to drill mine.Rockey ones seem quite rare and expensive ad its only really the outer nut I need. Does anyone know any older or more common models with a compatible nut, or the spec of the nut to just get an equivalent.

 

[barbagris]

PM WARP9.9 - he has a modified option. If it works on the 450bhp beastie - it'll do for the rest of us.

 

[JaMax]

Yes, that's the mod I intend doing but was hoping to pick up a cheap used nut rather than drill my own one so that I could put it back if needs be.

 

[Idaho Red Rocket 3]

Please post some details of this mod.

 

[JaMax]

As barbagris says, Warp is the main man for this mod but in a nutshell it consists of drilling and tapping the outer nut of the tensioner so the existing short pin can be replaced with a longer threaded bar. This allows you to retain the standard spring but screw the bar up to the tensioner blade so that it can't slip back on the ratchet.
I'm sure there will be details of it here somewhere but I couln't find it in the quick look I just had.

 

[warp9.9]

As barbagris says, Warp is the main man for this mod but in a nutshell it consists of drilling and tapping the outer nut of the tensioner so the existing short pin can be replaced with a longer threaded bar. This allows you to retain the standard spring but screw the bar up to the tensioner blade so that it can't slip back on the ratchet.
I'm sure there will be details of it here somewhere but I couln't find it in the quick look I just had.

If you are going to do the mod as mentioned above. Your new drop measurement for when to add the spacer in the plunger is now 13 mm this is becasue you loose the brass assemblyline retainer of the OEM one. ALso this is not ment in any way to be used to adjust the tensioner. Never force the jam stud to the bottom of the tensioner lightly screw it down to the bottom and then back it off 1/2 turn and lock it down.

This is just a safety stop to insure the tensioner does not fail causing catastrophic failure to occurr.
Use a 1/4-20 UNC bolt drill (ON CENTER) with a #7 drilll bit .201" diameter. NOT WITH A HAND DRILL.
TAP ON CENTER!!!!!!!
Failure to do this could reduce spring tension and proper aut adjustment of the tensioner!!!!!!!

I have 40,000 miles on this mod with no failure. Mine also has further modifications due to the heavier valve springs that come with the Carpenter Racing packages which are not needed with OEM springs.

 

[JaMax]

Thanks for the replies. Got a 1050 tensioner for £15 (the cheapest Rocket one I could find was £60) and modded the bolt last night.
Haven't fitted to the bike yet as need to move supercharger pipework but the modification was easy enough if anyone else plans on doing it.
Just drilled 5mm hole through top of bolt, knocked the pin out through the hole then tapped M6 for longer bolt.
I really like the fact that the tensioner still fuunctions as intended but with the added safety of a backstop.