Long rod pistons

Hey, hotdog. What's the story behind that 'ding' on the right chamber intake side? Will the headgasket seal that? Porting is such fun work. Did you match the intake spigots?
Hey, hotdog. What's the story behind that 'ding' on the right chamber intake side? Will the headgasket seal that? Porting is such fun work. Did you match the intake spigots?

That is from my clumsiness when drifting out the guides...dont worry a few words were said under my breath.:doh:
Thinking I might get the tig & fill/smooth it off..or maybe its more trouble than its worth.....:confused:

Intake spigots have not been matched yet, hopefully tomorrow. I'm using the TC bros/shell copies & need to see how the 36mm Dells sit in them.
Slowly unfortunately...I have recently received my rephased Shell #1 from Mrriggs & am about to order the gear I need to get this thing moving/finished.
Artistic shot


Pipes arrived from Gary Hoos Racing & intakes from Heiden Tuning ~ I couldnt resist a mock-up.


This will enable me to complete the cylinder head ~ R/D springs with Ti tops, MrRiggs rephased cam to 277deg & also reground to Shell #1 specs, 1mm o/s black diamond in & ex valves, Kibblewhite guides.


More progress soon ~ I hope......ciao
Hotdog......had to bump your thread and hope all is well an did you ever complete the engine build?
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Bumping this thread again:D

Hotdog,what compression height did you end having using the 18MM pins? Looks to be around .970 to 1.000. My Kz's will work just can't justify shaving the head .050 or spending big bucks for Total Seal rings to compensate for the compression loss.
Hi Jack, have you noticed I have commented in recent days.? Just so happens I have a small update for this thread - sorry its been a year since the last update.
The last year has been busy, both my father and grandfather have leukemia at the moment. Dads in remission but looks like the chemo drugs have damaged his heart and he is severely restricted in what he can now do.
And I have been struggling with some mild depression ( no drugs etc) sort of melancholy over the last year or so with a lot on my mind, but am doing good now and starting to get some work done on the bikes again - its my therapy. Im also about to go on a three week holiday with the wife and two kids, so life is good, anyway enough of the personal updates.

Barrels are back from the machinist bored to Ross's specs of .003"


The barrels have been decked, and that's about it, Jack cant remember C.H. but sounds close, hoping to get some traction on this real soon. Hopefully the next update won't take 12 months.

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Jack, CH is .985" see the below job sheet from Ross pistons. Job card # is there also - should you need it.
My thoughts and prayers go out to your Father and Grandfather and I hope your vacation is a safe one and that your recovery continues. I've been dealing with severe depression myself a few months back,had my life turned upside down but I'm slowly recovering.

Thanks for the Ross work order, my Kz pistons might not pan out,just not enough dome CCs in getting the compression up,has a dome height of .380 but not enough mass width wise. So I'll probably be ordering Ross slugs.
Jack ,these pistons are good for ~ 11.6:1CR
Approx 6cc's needs to be removed to get the CR down to ~ 10:1CR for street use.

These are not my calculations but Dave Rayner's, he had Ross pistons design these slugs for use with the CR500 rod.
See here halfway down the page.

BTW Jack, any comments or porting tips for my head will be appreciated. I have decided to go a little further with the ports as I was not happy with them, the guides were knocked out this afternoon.
First inspection reveals quite a lot of improvement to be had for little investment, guides will be shortened and have a 10deg taper machined on them. As well as further work on the guide boss area's.
Do you bore out the seat throat at all.?
I would use caution where you remove the dome CC's reason being you want the squish effect moving upward without resistance in it's path.

Give me an email for a photo in reshaping the intake guide boss area.

You'll gain alot more performance by D shaping the intake ports and when done correctly,port velocity shoots to the moon with absolutely no loss of CFM over a conventional round port on the XS. For example on the first D pull .100L -91,200L-132, 300L-170,400L-185,440L-198. These were with just the floor raised 3mm,roof lowered slightly and the short turned laid back and no guide boss work. Second pull the guide was shortened and boss area heavily trimmed,100L-80,200L-119,300L-181,400L-201,440L-205. The second pull will produce more power overall,thus help reducing reversion during the overlap cycle. So yes there are gains to be had in modifying the guide and boss area,my #s would vary from bench to bench but what your looking for are gains or a loss in the curve. The cross sectional area of the port is so ridiculous small,yet those ports pack a big punch and you can here it on the bench:D

The exhaust port with the least amount of resistance in the roof will always produce positive gains but yet is the trickiest to work with do to core casting. I'll try my best to post a picture of my long rod port.
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A small update, sizing things up and seeing what I'm missing to get this moving along again.
Have posted in the wanted section.

1st assembly, getting the lines right and seeing how things will sit.


Wheel building and truing, rear has a xs500 hub which incorporates a cush drive taking a lot of strain from the clutch springs (thanks "5twins"). Stainless spokes and 18" alloy wheels.