[motoguzzibill]

Winter Shop-work Time;
   After unsuccessfully solving a head gasket oil leak I've again pulled the cylinder head from my 06' Electra. On advice given by other members the cylinder has also been removed so that both mating surfaces can both be sanded/leveled with the hope of achieving oil tightness. I did notice that the cylinder liner "appeared" to not be evenly flush with cylinder face, either my imagination and/or Indian engineering.

  So I'm looking at the stock cast piston, which has very low miles, and wondering how robust and long-lasting is it? I do run the bike harder than stock having added BW's cams, "goldstar exhaust", Mikuni carb and a bit of port smoothing. So I'm already into the bike a bit and am deciding whether to swim deeper or get out of the water and sell before it explodes!

  I've long considered the 535 forged piston option and am seeking input from those who have made the plunge. Is it worth the effort and cost? If so there are two options; buy the piston and have my cylinder bored/honed or buy the piston cylinder kit, both available from Hitchcocks. (Are there any other sources to consider?) Best reasonable/cost effective option? Anybody have new/used parts available?

  Or is this 535 modification just throwing more good money down a hole? Will I be adding mechanical stress to a bottom end that is not built to take it? Why do we even spend time/money on such nonsense!!!
Appreciate your thoughts,
Bill N

[Bilgemaster]

"Why do we even spend time/money on such nonsense," you ask? Why, to make them better, of course. Now, what "better" may constitute is debatable. Some will see it as coaxing every last pony out of the paddock, striving for ever snappier performance, while others seek improved reliability and an extended service life. I'm clearly of the latter persuasion, not through any real virtue so much as by necessity. My now elderly 2005 "Iron Belly" is actually the newest vehicle I've ever owned. If I could trade one or two horsepower or, say, 5 mph off its top speed for an additional 25,000 miles of service life, I would do so in a heartbeat. In fact, I already did so with my ratty old Norton, pulling off one of its pair of carbs in exchange for a smoother-running less-stressed engine. You see, my great joy has always been resurrecting and then nursing along some greasy old wheezing geezer longggg beyond any reasonable expectation. Where's that sow's ear? Lemme have at it. That's had to be my motto most of my impoverished semi-nomadic life. Now it's just become another old habit.

But like I said, that's just one way of looking at things. I'm sure the more performance-oriented ton-up boys will be along directly with the other perfectly valid side of the story and good advice. They must just be off "flowing their heads" or something.

[Adrian II]

If the current head/cylinder barrel top surfaces aren't coping too well, losing an extra 1.5mm a side boring the cylinder out by another 3mm for the 87mm piston is going to help how, exactly?

If you **do** go for 87mm the 535 CGT piston is dished, which will help offset any slight compression increase caused by trying to squeeze an extra 35cc of mixture into the combustion chamber. If you're not already running B.W.'s trick of retarding the inlet cam by one tooth you can also give that a try, it will reduce the amount of incoming charge and give the engine an easier time.

I can't remember if it's you who is running a Hitchcock crank in your Electra-X, if it *is*, don't worry, just ride it. If not, er... how many miles has it done? 

Why do we even spend time/money on such nonsense!!!

How long have you got?

A.

[Bullet Whisperer]

Quote 'If you're not already running B.W.'s trick of retarding the inlet cam by one tooth you can also give that a try, it will reduce the amount of incoming charge and give the engine an easier time.'
 No, Adrian, it won't reduce the amount of incoming charge, just delay it a little and lower the cylinder pressure a little on the compression stroke.
 B.W.

[Adrian II]

Sorry, B.W.

But the trick certainly helped my AVL hybrid, as I think you know.

A.

[Bullet Whisperer]

That's ok Adrian, it seems to work on Electra X engines with 'S' cams very well. It also works on 500 'Iron' engines, whether tuned or not and on more highly tuned [but not standard] 350's, as standard ones just become rather gutless, where the 500's have the 'cubes' to deal with it. It also helps eliminate pinking [or pinging, if you prefer] 
 B.W.

[ace.cafe]

I think the 535cc is worth doing for the extra foot-pound or two of torque you can get from it. It also uses the larger AVL inlet port better with a little more inlet demand which will help out to get more ABDC ramming effects from the retarded inlet cam timing.
Every Fireball we have ever made includes the late inlet valve closing timing, and it has been very productive.

I would do the squish mod, and push the compression up as much as you can with that. The combustion chamber can handle more compression when it has the squish mod. If you want a flat top, we have tried the latest Wossner 87mm flat top piston, and it is now a fairly lightweight option. We have it in a Fireball 535 Continental GT, and it has done very well up to the 6500 rpms that we have done with it.

Remove the "hot tube" from the tail end of the header pipe, and get a free flow muffler.

Put on a larger carby, up to 36mm even, depending on how high you plan to rev.

This all should add up very nicely for power.
 

[Adrian II]

Ace, did you you ever get any more AVL heads Fireballed along the lines of tooseevee's? I know there were one or two hopefuls but I don't know if any more were actually modified.

As Bill already has a set of B.W.'s cams fitted I suspect he's also aware of the ASBO squish band mod for the Elextra-X/AVL engine.

A.

[ace.cafe]

Ace, did you you ever get any more AVL heads Fireballed along the lines of tooseevee's? I know there were one or two hopefuls but I don't know if any more were actually modified.

As Bill already has a set of B.W.'s cams fitted I suspect he's also aware of the ASBO squish band mod for the Elextra-X/AVL engine.

A.

Adrian,
There were a total of 3 AVL heads done with the full Fireball treatment and new combustion chamber design. The final result was similar to the later Ace Billet GT head design in terms of combustion chamber shape. It just got so expensive to do, that we could get better overall design from a new billet head at similar cost to what it was costing to modify the standard AVL heads.

[Adrian II]

I don't know how demand for your solid billet CGT heads is firming up, but I suspect the demand for solid billet AVL heads will be underwhelming!

A.

[ace.cafe]

I don't know how demand for your solid billet CGT heads is firming up, but I suspect the demand for solid billet AVL heads will be underwhelming!

A.

It would be the same item. It drops right on an AVL, if there was anyone who wanted one. Probably some experimentation with the oil squirter jets for the valve gear.

[motoguzzibill]

ACE,
  You refer to a  Wossner Piston, found this listing on Ebay, Piston Kit Yamaha YZ400 IT425 1977 77 1978 78 Over Bore 87mm, and am wondering if this is the piston you are referring to? If not could you be specific on which piston you suggest using. What piston/cylinder clearance do you recommend?

  Regarding the squish band, is this achieved by reducing/machining the cylinder base by 2mm or?
If the squish is increased will retarding the inlet cam (BW's) one tooth provide enough piston/valve clearance?

  Running the "stock cam settings" I found the inlet valve has been just kissing the piston top, leaving a small smile mark on the piston's forehead. Fortunately no valve damage. If I retain the stock piston I was considering grooving the piston top a few mm vs. retarding the cam. Thoughts/suggestions?

  I had previously tried backing the inlet cam back a tooth but found a flat spot developed in carburation that was very resistant to improvement despite jet and needle changes. Is this common or unusual?

  Appreciate the input and dialog. The sharing of knowledge/experience is invaluable.
Regards,
Bill

[tooseevee]

Adrian,
There were a total of 3 AVL heads done with the full Fireball treatment and new combustion chamber design. The final result was similar to the later Ace Billet GT head design in terms of combustion chamber shape. It just got so expensive to do, that we could get better overall design from a new billet head at similar cost to what it was costing to modify the standard AVL heads.

      I still carry some "head guilt" around with me to this very day 

[Adrian II]

Regarding the squish band, is this achieved by reducing/machining the cylinder base by 2mm or?
If the squish is increased will retarding the inlet cam (BW's) one tooth provide enough piston/valve clearance?

When B.W. turned my AVL hybrid into ASBO 12, he machined a 10mm wide by 2mm deep band off the outside of the piston crown and turned down the barrel base flange (and bottom of the liner) 2mm to match, with an additional shallow cut-out for the inlet valve head at my request.

Clearance was fine as a result, but as it ended up with a more-than-usual-AVL-ASBO-compression-hike (up to 10:1 from 8.5:1 instead of the usual 9.2:1, possibly due to different deck height of the non-AVL Bullet crankcase used), it still needed the "S" inlet cam retarding a tooth. That simple mod has definitely made it more pleasant to ride but with no obvious loss of va-va-voom off the line.

There is enough room in the combustion chamber opposite the spark plug for either a second plug if you're into twin-plugging or an old-style Bullet decompressor valve.

If I'm looking at the same ebay listing that you were, that Wossner piston looks like a two-stroke item to me.

The Hitchcock 535 Electra-X item even seems to have a shallow cut-out for inlet valve ready machined!



http://accessories.hitchcocksmotorcycles.com/accessory-shop/ELECTRA-X-Stage-2/11405

A.

[ace.cafe]

ACE,
  You refer to a  Wossner Piston, found this listing on Ebay, Piston Kit Yamaha YZ400 IT425 1977 77 1978 78 Over Bore 87mm, and am wondering if this is the piston you are referring to? If not could you be specific on which piston you suggest using. What piston/cylinder clearance do you recommend?

  Regarding the squish band, is this achieved by reducing/machining the cylinder base by 2mm or?
If the squish is increased will retarding the inlet cam (BW's) one tooth provide enough piston/valve clearance?

  Running the "stock cam settings" I found the inlet valve has been just kissing the piston top, leaving a small smile mark on the piston's forehead. Fortunately no valve damage. If I retain the stock piston I was considering grooving the piston top a few mm vs. retarding the cam. Thoughts/suggestions?

  I had previously tried backing the inlet cam back a tooth but found a flat spot developed in carburation that was very resistant to improvement despite jet and needle changes. Is this common or unusual?

  Appreciate the input and dialog. The sharing of knowledge/experience is invaluable.
Regards,
Bill

Otto used the Hitchcock one. I think that seems to be a safe bet,
Regarding clearance, I will ask him what he used.
Typically, .005" would be okay with a careful break-in on an 87mm forged piston in our application.

Regarding valve to piston clearance, you really need to check your actual engine because of variation in parts manufacturing. Try to get .060" on the intake for valve to piston. I use a soft clay pad 1.5mm thick on the piston crown and turn the engine slowly by hand, and look for a ding in the clay. Then measure the clearance from the bottom of the ding to the bottom of the valve relief in the piston crown.