Forum

[stinkwheel]

Cheers for that. Aye, I did a lot of thinking about oil feed with my other bullet and fitted a pressure relief valve from the get-go on this one. The feed side is fine, with the roller bearing crank it's effectively volume-fed, there is little resistance to oil flow. It's all about that scavenge pump. I was pretty thorough making sure the pump was entirely free to move too.


https://youtu.be/N1pUe9oW93E

[vince]

Hi, if you have fitted lengthened pushrods to match a lengthened barrel then the valve spring will be compressed the same as standard set up. The cam lift will effect how much the valve opens. Also if you have found metal in the filter bear in mind this will have to have passed through the feed pump.I would be inclined to think you damaged the pushrod by overreving on rhe misshift. Vince

[Bullet Whisperer]

Any metal particles from the pushrod failure will go from the timing chest, after being pulverized by the timing gears, back into the oil tank compartment, rather than being scavenged, but if they are small enough, the particles will get through the gauze oil feed pump suction filter, into the feed pump and into the big end, etc.

[Bullet Whisperer]

To add, hopefully your filter caught the particles.

[Adrian]

It's not made obvious in the current catalogue description, but wasn't the 90235 shrouded tappet adjuster kit actually developed for the Electra-X? The tappets on these have quite shallow concave tops to fit ball-ended adjusters on the push-rod ends, the opposite of the standard Bullet arrangement.



A.

[stinkwheel]

Well spotted on the shrouded adjusters. I'm convinced it's the over-rev that did it. I may even need to fit a rev counter (or possibly even a rev limiter, should be possible, It's electronic ignition).



I checked the feed pump and it's all ok in there and there was nothing in either gauze filter. Thanks for the help.

[Adrian]

The 612 inlet push rod is the same length as the Indian 350 exhaust. So if you buy the you-can't break-'em 90131 push rod set made in the USA from 6064-T6 alumin(i)um you will at last have ONE push road that will withstand your siding technique! ;o)



A.

[Adrian]

Sorry, ROD, not road. Too near bed-time.

[Presto]

I'm noting that the first posting said that the pushrods were set with 'slight clearance'. Does this imply some vertical movement (which there ought not to be) or that they were free to rotate without any vertical movement (which is correct)? I'd also add that in my experience these 612's definitely need 'old style' running in - but in any case 'caveat emptor'!

[stinkwheel]

The fitting instructions our hosts included with the kit listed a specific tappet clearance which I duly measured at the valve stem and set. It was enough to give a barely perceptible vertical movement on the pushrod.



re "can't break-em" pushrods. I suppose the trouble with those is, if they can't break and one jumps, will that move the fail point elsewhere (follower, rocker, crankcase!?). A rod is relatively cheap to replace.



Rev counter ordered. I'm looking into aftermarket rev limiters but I'm not sure how they'll play with my self-exciting electronic ignition.