Project update: very good, then a very bad day

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Mod to add screen to 72 oil return.

72 crankcase mod to add sump filter

The 72 cases were a backward step, the removal of the sump filter was the worst part of this. The current recommended mods cure the issue with the forward sump pickup not working at high revs by changing the location to the back. The lack of a sump filter can be partially covered by drilling a...
www.accessnorton.com www.accessnorton.com
 
I've a 750 standard bore barrel that suffered a drop ( not me ! ) and a bottom fin busted off. You'd have to make an iron fin and have it welded back on and ground . Plus I'm in Toronto and shipping the lump would be crazy. Find out more about re sleeving yours ? Nearby me Gord Bush Performance does re sleeving in his machine shop. I think there is a shop in California that does this too. Research.
 
Thanks everyone. It’s gonna be more than barrels I need. Bottom end is rough as well.
 

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Coolhands said:
Thanks everyone. It’s gonna be more than barrels I need. Bottom end is rough as well.
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At least the LH connecting rod did not gernade but keep going you need to split the cases. How is the cam? Do you have the slot across the teardrop on the Hepolite pistons?
good luck. Edit: I had to look again at the 1st image to get orientation.
 
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Sorry for all your troubles there Coolhands, but if I'm not mistaken those pistons look like the ones that used to separate in the oil ring land. So maybe there is some good ------well, I mean had the crown come off the head would be messed up too.
 
RGM sells new strengthened 750 barrels with the 850 type through bolt arrangement.
Unfortunately , they are a bit pricey at 595gbp.
On the other hand, even if it was possible, liners and machine shop costs would add up.
G81 is planning to offer
alloy 750 and 850 barrels sometime soon.
Motoparts in Edmonton show a used 750 barrel for $700 cdn, which is about 400 GBP.
Judging by the pricing, they are aware of the shortage of good used 750 barrels.
The strange thing is, the used 750 heads can be had for cheap whereas the 850 heads, especially RH 10, go for big prices on eBay.


Glen
 
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Coolhands said:
Thanks everyone. It’s gonna be more than barrels I need. Bottom end is rough as well.
Click to expand...

Which type of circlips were fitted?
If they were the wire type and not Seeger then that would probably explain what looks like damage from a loose circlip.
Unless the pistons have long slots behind the oil rings then they aren't the original weak type that the crowns often broke off.
 
Sorry to see that much damage! At least it's winter and not July Hope you got a Christmas Bonus!
 
There was no evidence of what pins were there in right piston. (second pic) the left piston had the good circlips…and all the skirt damage.

I’m in Florida so this IS riding season.
 
I think the price and the measurements on that eBay barrel are correlated. Lol
 
RGM lists sleeves for the 750.
Is it general knowledge the 750 doesn't sleeve well?
I'm not up to speed on that.
 
worntorn said:
You are correct. I had 74mm down as 750 stock bore , not 73mm!
Just as well passed up then.

Glen
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Ya, if it were .040 or less I probably would have snapped it up.

It sold for about $70 delivered. It might need to be bored - 0.080 over pistons are available - I wouldn't do that, but someone might.

I'm faced with building a basket case for a guy with a nice set of cylinders bored to match new pistons, but he had the cylinder powder coated by someone who didn't know what he was doing - the powder coating is flaking off and was applied very thick.
 
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