Topic: K1 Hot Rod the Rat Race, new/old stuff.

[grcamna2]

During a no sleep night I cruised ebay and found a set of wisco 836 new in boxes kit. There were 3 hours left at 4 am and no other bids so I did the minimum bid and got them paid for this morning. Just a tic over $300. I kind of wanted the CycleX 870 kit but I'm not sure if it requires top case boring, they're out of sleeves anyway and I really don't want to split this motor. 
 Anyway, I'll send Ken my best late 750 cylinder and get the deluxe bore/hone/mods package. I'm not sure if the cylinder in it now (was seized by barn rust) is early or late but if it's early I'll have big sleeves installed for the stroker motor.

Wisecos 
Don,what compression ratio are they ?

[Don R]

 10.25 to 1. Apparently, they spent a lot of time on a shelf.

 Today I popped the former turbo 836 cylinder into the gas grille, got it to around 350 and pulled the sleeves. The one sleeve that had already been replaced was a little difficult to pull. I merged a gear puller with a slide hammer and got it pulled while it was still hot.
  I'm hoping this cylinder will go on the 72 mm bore stroker motor, I'm counting on moving the existing  sleeves to this block. If not, I'd bet someone can sell and install new ones.
 
   I have a late cylinder for the Wisco 836 and an early cylinder for the as yet unknown cc turbo dragbike motor.
 These three motors and a stock diecast are the last projects I plan to rebuild.  But we know about plans.
 

[grcamna2]

When you get the projects finished and fine-tuned  Then you can spend more time taking them for rides and less working on them 

[Don R]

 Too many to keep running, many need a new home. I just happen to suck at selling.

[Jerry Rxman Griffin aka MuthaF'er]

Don, I think I'm sitting on 2 sleeves from Kenny that I got for the 890 before you sent your Abe kit to Jay.

[Don R]

 I bought a Wiseco big bore kit at 3 am off ebay this week, thinking it was 836, it turned out to be an 812 kit boxed in 1977. Everything is there including rings, pins and clips. The error is mine, I looked back at the ad and it clearly says 811.

[grcamna2]

I bought a Wiseco big bore kit at 3 am off ebay this week, thinking it was 836, it turned out to be an 812 kit boxed in 1977. Everything is there including rings, pins and clips. The error is mine, I looked back at the ad and it clearly says 811.

Will that work ok ?  What's the CR on those ?

[Don R]

  They will work, the comp is 10.25-1 I also have a set of used Venolia (RC) 12-1 812's. I'm wanting something bigger though, this particular motor has an RC315 cam, ported head, RC steel rods and header. I really want to do it justice.
  I'm still stuck on the 890 kit, it requires more machining for sleeves but not the top case.
  It's crazy thinking these pistons and rings have been kept nice in the box since the when 1977 K I have was new and still sitting in the showroom.
 

[Don R]

 I bought a Wiseco 836 kit off ebay tonight, it was way cheap. If it's the real deal, I'll share the info, for some reason it's difficult to find.

 Search Wiseco piston kit K836 $355.52 shipped from Motoparts Depot. I was suspicious because the site didn't want to let paypal work but I think if was due to me backing up to check again to be sure everything was new and included. The piston number is the same as other kits, I should get it next week since I purchased during the holiday.
 Now I have Wiseco 812 and 836 kits to build. 

[Don R]

 
  The Wiseco 836 kit arrived today, it even has a head gasket. 4 pistons, pins, rings and pin clips. The Ad didn't mention the gasket. I'd say it's the big bore deal of the year unless you get the China 65mm kit for $49.  I spent some time cleaning up a cylinder block so I can choose the best one.

[grcamna2]

 
  The Wiseco 836 kit arrived today, it even has a head gasket. 4 pistons, pins, rings and pin clips. The Ad didn't mention the gasket. I'd say it's the big bore deal of the year unless you get the China 65mm kit for $49.  I spent some time cleaning up a cylinder block so I can choose the best one.

Excellent Don. You got a picture ? 

[Don R]

 I do now, the piston tops look just like the old 812 kit only a mm bigger.

[PeWe]

That kit look newer with bar codes on packages.

[grcamna2]

A complete Wiseco 65mm piston kit 
Will this piston kit work together well with all the rest of the mods to this engine ?

[seanbarney41]

The Cometic brand head gasket that came with a recent Wiseco 836 kit looked like pure garbage...poorly shaped ill fitting bent up piece of cardboard.  Every where I tried to source a better one (CycleX, Dynoman)just kept sending the same thing.  Finally ended up getting a very nice Honda oem style one from Yamiya.  It seems to have worked well, although I have only put 20 or 30 miles on the engine before the weather got too bad.

[MauiK3]

Yamiya stuff is usually pretty good.

[Don R]

That kit look newer with bar codes on packages.

Yes, it's new from Ebay, $355.52 delivered by UPS. Sold by Moto parts depot. For some reason it's difficult to find this ad on ebay. Other sellers are $668 for the same kit. This Wiseco gasket package is pretty generic, says fits 811,836,849. 65.5mm  .043 thickness. I wonder if that's compressed?
https://www.ebay.com/itm/364044073950

 This motor has been an RC 836 until it stuck from its time in a barn with no carbs on it. The PO raced it and street rode it. Said he loved to pick on 900 Kaw's. I'm assuming the pistons grabbed the cylinder since it seized on me. I will use an O2 sensor on it's first ride to prove the old 29 mikuni carbs are right. I think the valves are stock size, head is ported, didn't find RC stamped on it anywhere yet. I have three of those heads, one fresh one has a small ding in the combustion chamber.

 I plan to check the valve / piston clearances and re-build it just like it is. After I took it apart and called him back, he confirmed that that's the good engine. L0L. The bikes came and went over the years and he was a little foggy about which motor ended up in it, the turbo 836 was in this frame too. I have a lightened rotor and an A alternator, hoping I can electric start and still stay light on the crank.

[PeWe]

The headgasket comments here forced me to leave the TV at my relaxing morning coffee wake up procedure!

Measured some gaskets I have.
The newer Cometic gaskets look different than before older graphite looking surface.
Now more like hard fiber with a waxy outside.

1.2mm thick and I think this will not compress.
I have used a similar looking stock size gasket from a Vesrah gasket kit with my K2.. Nuts did not move after 24 hours from first tightening with 21 ft lbs.




I measured CI 65mm gasket that look more as old Cometic and Yamiya 65mm gaskets. Soft surface that will compress, 1.4 mm now when new.
I doubt it will compress to 1mm. But might be possible. If it does, several retorques can be needed. After 24 hours each time


I have old 65mm gaskets that are 1.0mm thick when used. Maybe old Cometic or Yamiya. No photo.
I reused them as head protection when reshaped chambers with a flap sanding wheel to make them equal volumewise. (All valves might not sit at same height after seat jobs)

I also measured a few MLS gaskets. I have one closer to 1.2mm thick.




Important for my ongoing build where I have to use thicker headgasket and base.
Pistons are milled off 2mm, before double plug washers when pistons hit the electrode and compression too high

890cc cylinder has 0.8 mm deep o-ring groves for oil feed.
The total depth will be 0.8+1.2mm=2.0mm
Thicker o-rings needed.
Stock o-ring will make min 20% compression thanks to the milled cylinder.
2.62mm will do better,
23.66% compression.

That cylinder can not use head gasket thinner than 1.0mm without using thinner oil feed o-rings. 2.2mm thick o-ring needed with MLS 0.03" (0.76mm). If 11.5x2.2 mm is available.

The grooves are usually 0.9-1.0mm on those  cylinders I have measured.

If cylinder should not be milled: Only 16% compression despite 2.62mm o-rings with 1.0mm deep grooves in cylinder + 1.2mm thick head gasket!!!

- Head gasket 1.0mm thick:
- Grooves in cylinder 1.0mm deep.
- O-rings 2.62mm thick
2.62-2.0mm=0.62
0.62/2.62=0.2366-->23.66%

Headgasket can not be thicker than 1.0mm.
If it is, cylinder need to be milled off 0.2mm if o-ring grooves are 1.0mm deep to 0.8mm. this will make 1.2mm thick gasket usable with thicker o-rings.

The better way is to use MLS 0.03" thick,  (0.76mm)
Compression 29.6% when o-ring grooves are 1.0mm deep + stock 2.5mm thick o-rings.

I use the 2 o-rings with MLS just fore sure. The MLS gasket has sealing protrusions for all oil feeds and returns.

I have also drilled all stud holes in the head with 9.5mm drill to ensure oil to flow.

Some holes where around 8.5-9.0mm. Cannot be a good combo with 8.0mm thick HD studs.

I have calculated various situations in a thread where Hondamans recommendation of thicker o-rings came up.
http://forums.sohc4.net/index.php/topic,153549.msg2203559.html#msg2203559

Rubber compression is between 20-30% according to an o-ring seller
https://www.marcorubber.com/o-ring-groove-design-considerations.htm

I'll use fiber gasket to start with. 2.62mm o-rings.
Oil return holes need o-rings too. Cylinder is earlier with smaller holes, dia +10mm.

DonR:
Measure your head chamber volume. If more than 23cc use the thinner MLS 0.03". This will ensure compression.

Check cylinder height (stock 85mm)
You'll see the depth of oil feed o-ring holes. Stock 0.9-1.0mm as I have measured.
Check how high the pistons sit at TDC, max 0.25mm from mating surface down to pistons outer edge. This with base gasket.
Or easier to see without base gasket. If piston outer flat area is flush with mating surface: Really good, use thin RSC base gasket 0.25mm thick plus thinner MLS will make squish area to 1mm which is a good number.
This if the chambers are not widened.
If 65mm or more, the squish will be the piston dome vs chamber shape. An old ported head used with old big bore pistons are most likely widened.
If head height is closer to stock 72+ mm, mill it and chamber diameter will shrink, chambers reduce and fit 10.25:1 pistons better.

I let my shop shave off 0.5mm on an old ported K2 head to get chambers smaller for better squish with 71.25,  later 70mm pistons and better compression. Head height down to 71.1 mm that indicate old shavings. Total shavings 1mm 

My ported K6 head is 71.85mm where mating surface has been grinded several times before, an old stock K1 head 72.1mm.

[PeWe]

I had to check my o-rings too!!

I have 10.78x2.62 mm in both Viton 75 and Nitrile 90.

Next to o-rings for later fiber gasket with wider oil return holes to earlier cylinder.
Brown viton of unknown hardness 12.42x1.78mm will be used with my 1.2 mm fiber head gasket, not thinner. Compression a little bit high, 33%.
Good that I calculated compression so I do not use the 12.5x2.0  Viton I have wich is way to thick. For 1.4mm gasket.
Oil feed can not handle 1.4 mm gasket without milling cylinder 0.4-0.5mm so ring groove is 0.5mm.
Thick 2.62 mm oil feed o-ring needed.
Total depth then 1.9mm

Important use of o-rings avoiding future oil leak in a good running engine.
If rework and other adjustments needed no problem to change o-rings or gasket to a no leaking one.

Correct installed MLS is a better one regarding leaks in oil feed and returns.

I wonder if too sloppy compressed o-rings can be one reason why collapsing inwards blocking oil feed?
Oil pressure can creep under or over o-ring pressing inwards against head gasket hole.

It is easy and important to calculate o-ring compression rate. 20-30% according to the earlier mentioned site.

I have bad example using too thick cam tower o-rings around orifices, later head oil orifices. 6x2.0 mm viton not good.
Back to smaller closer to stock.  Nitrile 5.8x1.8mm I found cheap as 50 pack.

This could have cost me a cam tower, cam and rocker arms if rubber debris went inside blocking the oil. Not much needed.
Using CycleX by Web cam welded rockers.

[seanbarney41]

Damn PeWe, you have really put a lot of thought and real engineering into this.  No wonder your dyno results are so successful.  That first Cometic you posted a picture of sounds like the one I didn't like the looks of.  I have used Cometic brand gaskets on other bike builds that I thought were especially nice and worked great.  Just something about how differently constructed that Cometic was from an oem and the low quality fit and feel of it made me wary.  I have not heard of anyone having problems with them.  The Yamiya 65mm head gasket looked like very similar construction and materials as an original oem, which I know are good when treated properly, so I used it.  Can't wait for some better weather to get the bike tuned and put that gasket to the test.

[PeWe]

I wrote down my experiences with mainly my K6. Good to share with others. I can have a look later on too.

I'll see how the Cometic fiber gasket will work. I'll use it on my ongoing 890cc engine build that might need adjustments.
That's why I ordered several of gaskets to my 890. Also to 970 and 1005cc from Dynoman that has lots of different gaskets. Here in Europe not so much and very expensive. Better to fill the shipping cost with more parts.

Various issues demanding redoings and changes wich have the good side when it will become better and better
.
So a problem will usually end up in something better when fixed. That's part of the life as well Sometimes it take a while to see.

[grcamna2]

I wrote down my experiences with mainly my K6. Good to share with others. I can have a look later on too.

I'll see how the Cometic fiber gasket will work. I'll use it on my ongoing 890cc engine build that might need adjustments.
That's why I ordered several of gaskets to my 890. Also to 970 and 1005cc from Dynoman that has lots of different gaskets. Here in Europe not so much and very expensive. Better to fill the shipping cost with more parts.

Various issues demanding redoings and changes wich have the good side when it will become better and better
.
So a problem will usually end up in something better when fixed. That's part of the life as well Sometimes it take a while to see.

Definitely 

[Don R]

 I've decided to stop the turbo project and get this bike torn down so it may run this summer, it may be an 811, 836 or who knows. I thought I had the F1 sold and was determined to spend all the money on this motor.

 Anyway, the plan today is to get off my ass, clean the junk off the lift, get some parts boxes and begin a teardown including the frame kit and top end. I may or may not split the cases depending on how things look inside.

[PeWe]

When engine is out and cyl off, not much left to open the cases.
The oil seals might need to be replaced?
If they dry up when old, engine not used. Oil leak at ignition and/or front sprocket.

I have thoughts about a crank to be used in a build, if the seal in the starter gear must be replaced. Take off alternator for that. Over 45 yers old.

[Don R]

  Thanks,  I could use some problem saving advise.
  I've been looking at the cyclex 970 kit. If I go that way the top case will need to be machined.
  I actually have a lightly used K6 crankcase on the stand with a backcut F2 transmission in it and a balanced crank with MTC steel rods. I was going to use it in the turbo build, but this bike is ready to ride except for the motor. 

  One kit has the 970cc 10.25/1 pistons, gaskets, sleeves, and a cx11 cam. $1199 seems like a deal and $535 for machine work to my early cylinder. 
  Another option is to fix the sunken sleeves in the 1124 stroker motor and run it. It has (short?)
  aluminum rods and to remedy that will need modern sleeves, pistons and rods and that's still the old fashioned welded stroker. Or just fix the cylinder and be brave.