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I saw a fix to stop oil from going down the headbolt from the rocker cover on a T100r . It involved making a recess in the head for the four inner bolts and fitting an o-ring. I was sure it is on this site but I cannot find it. Can someone help me out? Thanks jerry
 

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I saw a fix to stop oil from going down the headbolt from the rocker cover on a T100r . It involved making a recess in the head for the four inner bolts and fitting an o-ring. I was sure it is on this site but I cannot find it. Can someone help me out? Thanks jerry
hi Jerry,

Try the guys at Vintage Triumph Supply who sell a "kit" as I understand it, a set of viton covered washers that form an oil seal.

johntioc has discussed these here, if you seach his posts, you'll find some reference to them. HTH. RR
 

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Hi Jerry,

I saw a fix to stop oil from going down the headbolt from the rocker cover on a T100r . It involved making a recess in the head for the four inner bolts and fitting an o-ring.
Not that exactly but I've posted similar details of a similar mod., not sure if it was here as well but definitely on BritBike.

Firstly, my mods. involved the rockerbox oil supply bolts, not the headbolts; if your bike has a leak from the rockerbox down a headbolt, ime that's either a gasket or rockerbox fault. :(

Otoh, if it's my mod. you're thinking of:-

. I replaced the standard 'thin shank' oil feed bolts with 'proper' banjo bolts - drilled down the centre to cross-holes matching the oil feed banjo and the rocker spindle hole.

. The new bolts are socket caps ("Allen") rather than hex. heads and also longer - I measured the head, rockerbox, oil feed banjo, copper sealing washers, (stainless) steel washers - to stop rotating bolt head or dome nut gouging the copper washer - 'heavy duty' (oblong section) spring washer and allowed for 1/4" protruding for the domed nut.

. I chose standard off-the-shelf 6 mm. nominal i.d. 'O'-rings, so the machinist could look up the various figures for the recesses in the head and rockerbox surfaces.

. Finally, when assembling with 'O'-rings, tightening bolts and screws squeezes the 'O'-rings, so the oil feed bolts can't be rotated without loosening everything again. So I had the machinist who did the new oil feed bolts mark the heads 180 degrees around from below the cross holes. So when a bolt is positioned during assembly with the head mark visible, I know the cross-holes are pointing at the ones in the oil feed banjo and the rocker spindle feed.

In addition:-

. I don't know whether you've noticed but, between the workshop manual and the parts book, the positions of spring washers and thrust washers on the rocker spindles are different? John Healy ("johntioc" here) has advised that the parts book is correct, thrust washers should be against the rockers, spring washers against the box.

. The rocker spindles should be scrolled to promote oil transfer along them; if the ones on your bike aren't, perhaps look into having it done next time the boxes are stripped?

Hth.

Regards,
 

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Actually this is often done on 1971-up 650 & 750 twins. Either by using a thicker head bolt washer cut for a seal, or by machining an "O" ring groove in the head. This is because the rocker box gasket does not seal the 4 inner head bolts as the earlier 650 and 500 twins.

ll you need is a proper gasket. Get a hold of the Bonneville Shop, or any of the 300 shops we sell to, and get a pair of our CovSeal rocker box gaskets. Clean the rocker box surface with denatured alcohol, check surface for flaws and DO NOT use any sealant.
John
 
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