Crunchies on the drainplug %^^&*&(

MS850 · Sep 21, 2016

Have fun on your trip, I calculated your 4500 mi turn around point is Portland Maine, Tabasco Mexico or Whitehorse :roll: Thats a big trip even for a modern bike

cjandme · Sep 22, 2016

MS850 said:
Have fun on your trip, ..........

+1 and thanks for this thread :mrgreen:

850commando · Sep 22, 2016

Jim now you show us the good stuff after my head is out the door...

that oring seal arrangement looks just right

comnoz · Sep 22, 2016

850commando said:
Jim now you show us the good stuff after my head is out the door...

that oring seal arrangement looks just right

Well, I am just about ready to find out....

fiatfan · Sep 23, 2016

+1 on that head job, beautiful work! But how do you keep the o-rings and copper rings from falling off when putting the head back on?
Tommy

NKN · Sep 23, 2016

fiatfan said:
+1 on that head job, beautiful work! But how do you keep the o-rings and copper rings from falling off when putting the head back on?
Tommy

For the o-rings, just oil them, for the copper ones ? ? ? A little grease ? ? ? Or event put them on the barrels.

Well, this idea came after a nice ti-punch, so it needs to be confirmed.

comnoz · Sep 23, 2016

fiatfan said:
+1 on that head job, beautiful work! But how do you keep the o-rings and copper rings from falling off when putting the head back on?
Tommy

The copper rings are a snug fit in the groove.
I use a little liquid Teflon sealer to stick the silicone O-rings to the head.

cash · Sep 24, 2016

Jim,
I do like your head sealing mod, it reminds me of the way GM seal their speedway engines. They use what look like Viton O rings even for the flame ring.

Do you think it might be worthwhile to put an O ring round the oil return hole ?

Dave.

comnoz · Sep 24, 2016

cash said:
Jim,
I do like your head sealing mod, it reminds me of the way GM seal their speedway engines. They use what look like Viton O rings even for the flame ring.

Do you think it might be worthwhile to put an O ring round the oil return hole ?

Dave.

The oil return hole is sealed by the oustide o-ring like the pushrod holes. Jim

CanukNortonNut · Sep 24, 2016

comnoz said:
Now for the tricked out head. 3.5mm oversized intake valves and a full street port job. Grooved for silicone o-rings with copper rings around the bores. No head gasket. Inserts for 10mm plugs.

The nice change is a 75+ degree drop in head temperature at 75mph. That should help my oil life.
Jim

Jim,
The hole at the front center, outside of the sealing area… looks like a Ludwig idea?
What’s the rear 1/2inch ish hole for? just outside of the sealing area. Is it for the same reason? :idea:
It also looks like you flycut a little more than 0.040" aka combat style off the gasket base material. Or is it just the casting? Very interesting.
Cheers,
Thomas
CNN

Danno · Sep 24, 2016

fiatfan said:
[quote: Maybe elliptical pistons might be on the agenda :shock: quote]

Pete

Honda tried that in road racing back in the 90:s (?) with a 2-stroke 500cc, oval pistons, 2 cylinders and 4 comb.chambers. Didn't work.....
Tommy

It was a 4-stroke, 4 cylinder engine. The goal was to make a V4 breathe like a V8 with 8 valves per cylinder, two connecting rods per, effectively making a V4 into a V8 with only 4 combustion chambers. And it did work, it just wasn't enough to compete with the 2-smokes.

comnoz · Sep 24, 2016

CanukNortonNut said:
comnoz said:

Now for the tricked out head. 3.5mm oversized intake valves and a full street port job. Grooved for silicone o-rings with copper rings around the bores. No head gasket. Inserts for 10mm plugs.

The nice change is a 75+ degree drop in head temperature at 75mph. That should help my oil life.
Jim

Click to expand...

Jim,
The hole at the front center, outside of the sealing area… looks like a Ludwig idea?
What’s the rear 1/2inch ish hole for? just outside of the sealing area. Is it for the same reason? :idea:
It also looks like you flycut a little more than 0.040" aka combat style off the gasket base material. Or is it just the casting? Very interesting.
Cheers,
Thomas
CNN

The front hole is a Ludwig idea. The hole at the rear is where I route the wire for the temperature sensor.

It's a Fullauto head with lots of material to start with.

I cut .085 off the head, .045 off the barrel and with no head gasket I got the compression up to 9 to 1 with the dished pistons. I am using a .020 Cometic base gasket. Jim

CanukNortonNut · Sep 24, 2016

Oooh what a test mule you ride. :mrgreen:
Are you going to the LOP and then Barber with this?
Cheers,
Thomas
CNN

Hortons Norton · Sep 24, 2016

Nice work, Thanks for sharing.

comnoz · Sep 24, 2016

CanukNortonNut said:
Oooh what a test mule you ride. :mrgreen:
Are you going to the LOP and then Barber with this?
Cheers,
Thomas
CNN

That's the plan.

74ok · Sep 25, 2016

comnoz said:
I cut .085 off the head, .045 off the barrel and with no head gasket I got the compression up to 9 to 1 with the dished pistons. I am using a .020 Cometic base gasket. Jim

new to me, just some fill for us noobs - Cometic base gasket

http://www.cometic.com/

repair-101-gasket-help-t20184.html#p260498

The best gasket type I have used on any type engine is the Cometic type. This is a thin aluminium sheet with rubber sprayed onto each side. Totally reusable, seals perfectly every time.

https://www.google.ca/search?sitesearch ... jwTfkL7QBg

https://www.google.ca/search?sclient=ps ... norton.com

850commando · Sep 25, 2016

Jim do you attribute the 75deg drop in temp to the new new pistons and the lightly freshing up? i'm not assuming that the temp drop is due to the gorgeous oring seals (replacing a more normal flat gasket).?

comnoz · Sep 25, 2016

850commando said:
Jim do you attribute the 75deg drop in temp to the new new pistons and the lightly freshing up? i'm not assuming that the temp drop is due to the gorgeous oring seals (replacing a more normal flat gasket).?

I suspect the temp drop is mostly because I lowered the compression ratio from 10.2-1 to 9-1

NKN · Sep 26, 2016

Could deserve a new topic but like we are talking about it here... Heat, heat dissipation, barrels distortion...

Head being one of the hottest part of an engine, do you think that having a standard head seal will reduce heat dissipation into barrels much better than copper ones? And avoid distortion?

comnoz · Sep 26, 2016

NKN said:
Could deserve a new topic but like we are talking about it here... Heat, heat dissipation, barrels distortion...

Head being one of the hottest part of an engine, do you think that having a standard head seal will reduce heat dissipation into barrels much better than copper ones? And avoid distortion?

For several years I have had one thermocouple in a hole drilled into the head from the rear to a point between the bores about 1/4 inch above the gasket surface and a second thermocouple in between the bores in the barrel two fins down. They tend to run about the same temperature. The head temp just changes a little faster when you crank the throttle and the barrel temp catches up shortly.

I have not seen a change in that behavior since I eliminated the head gasket.

I have never run the engine with a composite gasket, so I can't say much for sure -but I suspect the top of the barrel would still run close to the head temp. The lower part of the barrel is always much cooler.

Bore distortion has not been a problem with the iron barrels.

I have seen less warping of the head gasket surface since I went to waisted headbolts however. Jim