Author Topic: 67.5 mm =cc?? (Read 5093 times)

lash · « **on:** November 24, 2019, 03:37:43 PM »

836 is 65.5 so what would 67.5 be?

754 · « **Reply #1 on:** November 24, 2019, 05:35:58 PM »

836 Is 65mm I think. 67 .5 is around 890 or 915 ish. And will require sleeves, and maybe case boring.

Terry in Australia · « **Reply #2 on:** November 24, 2019, 05:42:51 PM »

901.77cc.

http://performancetrends.com/Calculators/Engine-Displacement/Engine-Displacement.php

lash · « **Reply #3 on:** November 24, 2019, 05:48:50 PM »

I picked up a bunch of engine parts last year and there was a box with cylinders and brand new pistons and rings. Just finally looked at it today and the ring boxes are labelled 67.5. Bore measures the same. Pics tomorrow, maybe somebody an identify the pistons..

754 · « **Reply #4 on:** November 24, 2019, 05:52:21 PM »

Better tell us if cases are bored, if they are not its step sleeves, probably a Henry Abe kit.
If sleeve bottoms are same diameter as stock, I will guess Henry Abe with cast pistons.

lash · « **Reply #5 on:** November 24, 2019, 05:58:56 PM »

I’ll post the pics tomorrow

Terry in Australia · « **Reply #6 on:** November 24, 2019, 07:33:30 PM »

I'm betting Henry Abe too.

Tracksnblades1 · « **Reply #7 on:** November 24, 2019, 09:19:42 PM »

Quote from: lash on November 24, 2019, 03:37:43 PM

836 is 65.5 so what would 67.5 be?

Quicker....?

😎

PeWe · « **Reply #8 on:** November 25, 2019, 12:05:51 AM »

Important to be aware of the reall cc when ordering rings from CycleX to their "915cc" kit that use 67.5mm pistons. It should be called 900cc.

Dynoman sell a real 915cc kit, 68 mm pistons and sleeves that must have case bore.

PeWe · « **Reply #9 on:** November 25, 2019, 12:07:05 AM »

Quote from: lash on November 24, 2019, 03:37:43 PM

836 is 65.5 so what would 67.5 be?

65.5 is 849cc

lash · « **Reply #10 on:** November 25, 2019, 08:08:32 AM »

Here are the pics.

PeWe · « **Reply #11 on:** November 25, 2019, 10:47:56 AM »

Im sure other guys soon will chime in with exact description of those pistons that look like old design.

You will need better rods if using that kit

Like APEs rods.

Jerry Rxman Griffin aka MuthaF'er · « **Reply #12 on:** November 25, 2019, 02:06:06 PM »

What makings are inside the pistons. HAINST is Henry Abe. They made 2 different pistons in their kits.

lash · « **Reply #13 on:** November 25, 2019, 02:47:00 PM »

Only markings I could find...

Jerry Rxman Griffin aka MuthaF'er · « **Reply #14 on:** November 25, 2019, 03:23:41 PM »

I think that pic eliminates it as a Henry Abe. Possibly a CycleX? Can't say as mine are inside my engine. I do have the ring box at home.

754 · « **Reply #15 on:** November 25, 2019, 08:22:57 PM »

There is a W on the pin boss, looks like maybe Wiseco..

lash · « **Reply #16 on:** November 27, 2019, 02:10:33 PM »

Any idea on what this would be worth? I dont really want to get into big power parts, the engine I’m building is going into a bike for my wife..

Terry in Australia · « **Reply #17 on:** November 27, 2019, 05:05:27 PM »

It looks like they've installed bigger sleeves so whoever buys it will have to have their top case machined to accept them, plus heavy duty rods etc. Because of this they won't be of interest to someone looking for a cheap HP gain, when an 836cc kit will give them almost as much grunt without the big increase in cost.

If someone is going the high HP route they might prefer a more modern kit (I could be wrong but the ring lands look like they're set up for 1 piece oil rings, which are not ideal) but for someone not as picky, that is still a good kit, so maybe 200-300 bucks?

lash · « **Reply #18 on:** November 27, 2019, 05:13:34 PM »

I have the head for this but didnt check it to see if it has been machined. Will do that tomorrow.

Terry in Australia · « **Reply #19 on:** November 27, 2019, 05:17:43 PM »

No worries, take a look at the ports too, if it's been ported nicely, it may be of more interest than the big bore kit.

BPellerine · « **Reply #20 on:** November 27, 2019, 05:24:33 PM »

xc rings are weisco,and not 1 pc oil rings so modern pistons,put a bigger base gasket on and use as a template and grind away.bill

lash · « **Reply #21 on:** November 27, 2019, 05:56:43 PM »

Not sure what you mean about bigger base gasket and grind away?

Terry in Australia · « **Reply #22 on:** November 27, 2019, 06:54:06 PM »

Quote from: lash on November 27, 2019, 05:56:43 PM

Not sure what you mean about bigger base gasket and grind away?

The "Blue Ridge Mountain engineer" method of boring each cylinder hole in your top case is to put the oversize base gasket in place, mark the cases tracing the bigger holes, remove the gasket and get stuck into it with a die grinder or dremel tool, File, Bowie Knife, or whatever cutting instrument you have available, usually conducted while drinking moonshine and wearing Dickies overalls and a straw hat.

PeWe · « **Reply #23 on:** November 27, 2019, 08:55:43 PM »

Sure case need to be opened up for sleeves? The sleeves look thin as the tapered sleeves look like with 67.5mm bore.
My K6 needed a little Dremel massage while my K2 did not.

754 · « **Reply #24 on:** November 27, 2019, 09:59:38 PM »

I told him, measure or compare to stock sleeves..
Or look at holes in the case, stock I believe are unmachined..
Am I the only one that sees the W ?
I might be interested in them , I would have stock parts to trade towards. And I am in Canada.

lash · « **Reply #25 on:** November 27, 2019, 10:06:47 PM »

It will be a while before I can measure the case... $:-\$

BPellerine · « **Reply #26 on:** November 28, 2019, 08:29:18 AM »

Quote from: Terry in Australia on November 27, 2019, 06:54:06 PM

Quote from: lash on November 27, 2019, 05:56:43 PM
Not sure what you mean about bigger base gasket and grind away?

The "Blue Ridge Mountain engineer" method of boring each cylinder hole in your top case is to put the oversize base gasket in place, mark the cases tracing the bigger holes, remove the gasket and get stuck into it with a die grinder or dremel tool, File, Bowie Knife, or whatever cutting instrument you have available, usually conducted while drinking moonshine and wearing Dickies overalls and a straw hat.

haha,just one way of doing it if you dont have access to a good machine shop,could be tapered sleeves,cyclex?made pistons to clean up a 67mm bore,with 67.5,I think they also made tapered sleeves,as did henry abe which I have.bill

754 · « **Reply #27 on:** November 28, 2019, 10:13:38 AM »

You mean stepped sleeves.
I got to ask the OP, when you measure the pistons, has to be at the skirts, 90 degrees to write pin... not sure where you measured.

PeWe · « **Reply #28 on:** November 28, 2019, 12:07:24 PM »

CyckeX still sell that kit with 67.5mm Wiseco pistons and sleeves. CR 10.25:1They call it "915cc" which is not correct, diam is.

They sell 890cc too. CR 12.5:1

lash · « **Reply #29 on:** November 28, 2019, 01:42:25 PM »

more pics. The case is from an old 71 stock engine and the cylinders fit with no grinding.

lash · « **Reply #30 on:** November 28, 2019, 01:45:14 PM »

more...

BPellerine · « **Reply #31 on:** November 28, 2019, 02:01:40 PM »

then they are stepped sleeves as Frank said,I think 67.5 is the limit for those sleeves so they are a one shot deal,no more overbore.bill

754 · « **Reply #32 on:** November 28, 2019, 03:24:21 PM »

Looks a lot like a 77 or 78 F head. Look on the top back of head for number between 2 and 3 cylinder, it should say 410 or another number.

PeWe · « **Reply #33 on:** November 28, 2019, 08:46:00 PM »

Head ported too?

lash · « **Reply #34 on:** November 29, 2019, 06:39:12 AM »

Says 410. Dont know what a ported head looks like but this is no.2 intake..

Old Scrambler · « **Reply #35 on:** November 29, 2019, 07:12:36 AM »

Looks like it was 'cleaned-up' but not really ported..........Is there any machining to the chamber?

Jerry Rxman Griffin aka MuthaF'er · « **Reply #36 on:** November 29, 2019, 07:57:08 AM »

Good start on a HP engine. Big pistons and big valves. Big cam?

lash · « **Reply #37 on:** November 29, 2019, 08:22:18 AM »

I never got the valves or a cam with it. I’m not really interested in building a big power engine, these just came with the package.
My stock bikes are fast enough!

Terry in Australia · « **Reply #38 on:** November 29, 2019, 02:31:40 PM »

Yeah, the F2 head is no real performance improvement really as the negatives outweigh the positives.

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Author Topic: 67.5 mm =cc?? (Read 5093 times)