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Discussion Starter #1
Getting ready to finish the reassembly of the 650 engine that had come with a 'stalled restoration' project. The bores have redone 10 over, NOS pistons and rings, new Amal carbs. I have not unpacked the lower part as it is packed with oily rags and I dot not want to disturb that until it is in the shop I am reassembling it (maybe I should before). My question is, I am planning on getting new bolts etc. The 'kit' is also missing the pushrods so I need to source those as well. Someone had mentioned two piece studs to make reassembly with rocker covers easier. First motorcycle engine rebuild for me. What should I look for/buy so that they will fit this engine?
 

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You'll only need pushrods if someone lost or damaged the old ones.

Coventry Spares Ltd ,MA ,phone : 1-800-451-5113 ,offer a stud kit,to replace the original 3/8" bolts inside the rocker box.You'll need washers too,same as washers on outer head bolts.They can supply good pushrods,rocker gaskets,etc.
They normally deal wholesale,but give it a try.If necessary,your dealer can contact them.

If you need valves and guides,it's hard to beat Kibblewhite (KPMI).If you need valve springs,try to get standard springs,not aftermarket.
 

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Discussion Starter #3
Thanks for the tips. I have book marked the Kibblewhite site. The bike came with Springs but I do not reuse them in my MG engine rebuilds either. The bike did Not come with the lifters (or one of the lifter tubes). I figure to replace the headstuds as well.
 

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The bike did Not come with the lifters (or one of the lifter tubes).
The valve springs will be fine if they measure up close to spec on free length.I still measure the fitted load ,with bathroom scales,before pulling them out.
Even if they're 1/16" short,you can still shim them to get 65 lbs intake,75 lbs exhaust seated.That's enough for 8000 rpm,and you shouldn't be going past 7000.

When you say "lifter" do you mean pushrod or tappet/cam-follower?You can't mix up cam followers.If they don't go back in the same position and direction,they should be re-ground and re-bedded at 2000 rpm (no less) after you coat them with cam-lube.
 

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Discussion Starter #5
Thanks for the time. The head is disassembled already but I believe I have all the springs in a zip lock bag. Can they be measured in this state? I would think so. No pushrods came with the bike. Those I will have to source. Valves came with bike but I assume the consensus is to replace them.
 

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Valves came with bike but I assume the consensus is to replace them.
That would depend how the valve-stems and guides measure up.
Specs for a new engine:
Intake guide clearance 0.0027"-0.0042"
Exhaust guide clearance 0.0032"-0.0047"

It's not worth worrying about the clearance until it exceeds 0.008" at top and bottom of the guide.Even then,you might only replace the guides.There are other easy ways to reduce oil consumption through the guides.

Measure the free length of the springs.Even new springs won't always give the required seated load,depending on valve seat recession.You're likely to need a shim under the lower spring collar.
 

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Discussion Starter #7
Thanks for the info. I will save that and get some measurements. If I do not have to replace that would be great for my wallet!
 
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