Pretty nice barn find!!!!!

[Guest]

Nice Chuck, looking real good!

[chuck hahn]

Thanks guys on the likes.

Frank...I work Saturday afternoon so I wont be around. I will PM you.

Bill...I am not gonna sell it. I feel there arent that many still up and running. That alone adds some value to it I would think.

I still have to clean up the exhaust and put everything back on the bike.but the major stuff is finally all done.

[chuck hahn]

Maybe sometime next week I can recruit Frank to help me set the engine back in the frame.

I will then roll her out into actual sunlight for some much better pictures..which i think will show just how nice it really looks in person. I am very pleased with the way it turned out.

I gotta give props to my buddy Ron Watson for doing the cam cover for me. The original cover was chromed and that meant the fins had to be polished in between them also. I dont have a Dremel, so Ron took that aspect on and done one helll of a great job. Many thanks to him for the help.

[chuck hahn]

Went this AM and polished the exhaust with my Buschs Super Shine Aluminum Polish (works great on chrome as well ) and also cleaned up the exhaust crossover manifold. Next is to repaint the driver foot rests. Little things here and there need cleaned still but I am basically ready to put it all back together.

[chuck hahn]

Here is the exhaust crossover. It is a hollow tube that both exhaust ports empty into and then its vented to the pipes..dont ask me why because i dont have a clue why they did this!!!!

I used Aluminum Jelly and a green scrubbie to get in between the cooling fins..yes cooling fins IN the exhaust train?????

[chuck hahn]

Got some new black vinyl tubing and resleeved the ground cable and the starter cable and installed them on the engine.

I took welding wire and ran it down the tubing and fastened it to the ringlet on te end of the cable. Then wrapped the wire around a pair of pliers and stood on the pliers. Next, I just pulled and worked the new tubing over the cables.

She is ready to go back in the frame soon.

[chuck hahn]

I took the top end off again a few weeks ago because I had FINALLY found a NEW D.I.D cam chain and I also decided to put in new rings ( since it was gonna be back open ). Got all that done yesterday and today It will be reinstalled in the frame and I should have her fired again by early afternoon.

[Guest]

Here is the exhaust crossover. It is a hollow tube that both exhaust ports empty into and then its vented to the pipes..dont ask me why because i dont have a clue why they did this!!!!

I used Aluminum Jelly and a green scrubbie to get in between the cooling fins..yes cooling fins IN the exhaust train?????

Chuck - I would imagine its a motorcycle equivilant of an "H" pipe in the automotive world. In the mid-late '60's they were added to the high performance cars from the factory to not only equalize pressure, but it was found that the "H" pipe added some horses, but mainly it upped torque. There was a ton of science and trial and error to find the most advantageous spot for the "H". In most cars it was easier to put it in the intermediate pipes. I would think Yamaha put it so close to the head for easy of mounting and simplifying the exhaust instead of having header pipes, "H" assembly and then the rest of the header/exhaust.

The GS' have theirs under the engine. Whether it adds any punch, it must as the manufacturers wouldn't add it for looks alone. But that close to the head as the Yamaha has - I don't know.

I do know it could add up to 15-30 horses in a big block and around 30 or more ft/lbs. of torque. It went crazy the last few years and there's now "X" pipes and all sort of weird combintaions - all claiming to be the best.

[chuck hahn]

Thanks for the explanation Mike. Now once you mentioned the way our GSs are set up i see what it does.

Wel, Its running and all thats left is to fine tune the timing. Its 90 out right now and my gallon of water I took with me was gone, so I called it quits for today. Just a little more tinkering and she will be done as far as the engine goes.

Last thing that needs to be done is repolishing the fork lowers..but thats yet another day too.

[850 Combat]

BSA and Triumph had a cross pipe by the head from 1970 on. Norton did it in '73. On the bikes, I think it was done to make them quieter. Or at least a less restrictive exhaust could be used at any given noise level.

[Guest]

Any new images for our viewing pleasure Chuck?

[viperg]

Motor looking sweet! Nice work.

[chuck hahn]

I am going over in the morning before its 90 again and do the timing and put the side covers back on. I will take the camera with me.

[Guest]

Daggum' Chuck, hurry up and get this thing finished so we can find out how much money you're going to lose when you sell it. The suspense is killing me.

[chuck hahn]

Well I got just over 800 into it so its not a money pit. And for your information...its not gonna be sold.

EDIT...And that includes the 500 I paid for it..so 300 bucks to redo the top end isnt that outrageous.