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

[PeWe]

If it was a smoker, maybe guide seals.
If it smoked constantly or at start-up and little more.

[Don R]

 Agreed, this head may be set aside, it's used and stock, The stash included a fresh and used head both ported and the intake valves unshrouded. The fresh head already has an RC315 cam in it, there is still yellow assembly grease on the valve stems.
 I'm considering just setting this one aside and building the K6 case with the F2 backcut trans in it. It has a balanced crank and MTC steel rods. I was going to put it in the turbo bike but one thing at a time.

[Don R]

  The more I look, the more I'm sure it is new rings on an old cylinder. Maybe it was just assembled to keep the parts together. There was more plastic in the oil then there was in the pan, it's not from the cam chain tensioner so we shall see.
   I'm going out of town for a week starting sunday so I don't want to order a bunch of stuff and have it sitting out front all day and night. Maybe I can pull the motor tomorrow.

 Pic. to remind me why I'm doing this. I was surprised how much rust came out of the RC pipe, I'm going to see if I can treat the inside with the Eastwood's header paint. It has a big baffle inside and sounds really good.

[Don R]

  There were long thin straight pieces of black plastic in the oil, Forensics says he most likely had a chain guide come apart and then it was forgotten after a long delay re-assembling. This week I'm on vacation, next week I can push purchase on the parts in my shopping cart.

[Don R]

 I've been under the weather all week but made it out to the shop today. I noticed how heavy the RC engineering muffler was when I removed it so I pulled the baffle expecting to find oil and carbon laden fiberglass packing. Nope there wasn't any packing at all and pretty clean inside, it's just that heavy.
 So, I polished it, packed the baffle with fiberglass and put it back together.

[Don R]

 I got a new cam chain guide from Marks off of ebay. Formerly JT, now I think it's his daughter.

[grcamna2]

I got a new cam chain guide from Marks off of ebay. Formerly JT, now I think it's his daughter.

I'm glad she's continuing that 

[Don R]

 I think this one can take a hone job and new rings, a cam chain and guide and go back together. The money is going into its brother from a previous owner. 

 Cylinder base gaskets are on the way, I had an 836 head gasket already,

[Don R]

 I removed the old 836 piston rings today, the 3 piece oil rings had a couple bites taken out of the outer edges. I'm not sure if that was the reason it was stuck, or the result when I oiled it up and rocked it loose. I did notice the bottom of the cylinders had no taper ground in them to help with assembly.
 It has an RC315 cam, I'm wondering if the lift is high enough to cause the problem at the valve seals. The new head is already rebuilt. I'm hoping it works OK, wondering if I should find some weak springs to check it with. 

[PeWe]

If cam lift vs guide seal is the question. 315 cam has not that high lift, 0.368" minus 0.012" (0.3mm) lash.

Remove spring and measure between seal and valve stem groove for keeper. K valves have very tall groove and will enter the seal if guide is not sunken in head.

I got heavy oil consumption when distance was around 9.6-9.7mm, cam lift +9.8mm with running lash.
Guides not enough sunken in head for 125-75 or RC295 with 10mm in lift.

[Cut new stopper groove in guide to let it sink in deeper. Cut guide on orher side and reshape it.
Or use CycleX guides for higher lift. ]

I measured an old stock head where distance were around 9.2mm. Maybe that's why Webcam make low lift cam profiles only?

Photo of a severe oil drinker that became worse and worse. A liter or more disappeared really quick on a ride. Called my wife to enter the garage and grab oil and drive the car to where I have stopped before oul light kicked in. I saw in time that oil disappeared.
Guides are sunken deeper now. Closer to 12mm than 11mm seal-groove.

Below an old stock head with not sunken guide.

#
#
F2 valves have different groove for keepers.

[grcamna2]

If cam lift vs guide seal is the question. 315 cam has not that high lift, 0.368" minus 0.012" (0.3mm) lash.

Remove spring and measure between seal and valve stem groove for keeper. K valves have very tall groove and will enter the seal if guide is not sunken in head.

I got heavy oil consumption when distance was around 9.6-9.7mm, cam lift +9.8mm with running lash.
Guides not enough sunken in head for 125-75 or RC295 with 10mm in lift.

[Cut new stopper groove in guide to let it sink in deeper. Cut guide on orher side and reshape it.
Or use CycleX guides for higher lift. ]

I measured an old stock head where distance were around 9.2mm. Maybe that's why Webcam make low lift cam profiles only?

Photo of a severe oil drinker that became worse and worse. A liter or more disappeared really quick on a ride. Called my wife to enter the garage and grab oil and drive the car to where I have stopped before oul light kicked in. I saw in time that oil disappeared.
Guides are sunken deeper now. Closer to 12mm than 11mm seal-groove.

Below an old stock head with not sunken guide.

#
#
F2 valves have different groove for keepers.

PeWe,the top picture you posted which shows the long keeper grooves in the valve stem and the damaged valve guide seal;which model is that cylinder head from and which guides were installed then ?

[PeWe]

That picture from the 392 head.
Seal look a little bit sloppy when it is removed compared with a new.

Seal will not go that bad, only sloppier hole.
Most oil pumped in via the slit that occur when the groove goes inside, inlet will suck oil into chamber like a pump.

Remove spring and check your head. In and EX.
If clearance is small, use a lower lifting cam with matching clearance.

I read somewhere that the clearance need to be cam lift + 0.5mm.
After my episode cam lift + >1.0mm to feel safer.

If guides are new, they can be removed, cut a new stopper groove for clip, back in with the guide.

My local shop did that on my 392 head that had gone around 4000 km. Glass beaded and marked guide how it sat before. Then back oriented exactly the same when pressing it in, deeper this time.
I think he reshaped the tip in chamber side too, removed ca 1 mm that came deeper in.

That mechanic loves his job and can do lots of magic really quick. Done that since the 70's and is +70 yo.

Not much visible here, modified Honda stock guide.
Valve is Kibblewhite 33.5mm
This head is used now with 970cc, 125-75 cam.

[grcamna2]

That picture from the 392 head.
Seal look a little bit sloppy when it is removed compared with a new.

Seal will not go that bad, only sloppier hole.
Most oil pumped in via the slit that occur when the groove goes inside, inlet will suck oil into chamber like a pump.

Remove spring and check your head. In and EX.
If clearance is small, use a lower lifting cam with matching clearance.

I read somewhere that the clearance need to be cam lift + 0.5mm.
After my episode cam lift + >1.0mm to feel safer.

If guides are new, they can be removed, cut a new stopper groove for clip, back in with the guide.

My local shop did that on my 392 head that had gone around 4000 km. Glass beaded and marked guide how it sat before. Then back oriented exactly the same when pressing it in, deeper this time.
I think he reshaped the tip in chamber side too, removed ca 1 mm that came deeper in.

That mechanic loves his job and can do lots of magic really quick. Done that since the 70's and is +70 yo.

Not much visible here, modified Honda stock guide.
Valve is Kibblewhite 33.5mm
This head is used now with 970cc, 125-75 cam.

The 392 head is from a K7 or K8 ?

[Don R]

 F0, F1, K7, K8 have the 392 head, it's a little bigger chamber than the early head but way smaller than the F2/F3.
 I believe the pistons for the 392 may be used with an early head for a compression increase.

 Edit; I was wrong, I saw 405 as the head number on late K's

[grcamna2]

F0, F1, K7, K8 have the 392 head, it's a little bigger chamber than the early head but way smaller than the F2/F3.
 I believe the pistons for the 392 may be used with an early head for a compression increase.

Don,that you mention it,what about the head/chambers for the F2/F3 ? Do they need a high dome piston for increased compression ?

[PeWe]

392 head perfect with flat 12.5:1 pistons that can be milled as needed.
My flat JE 70mm pistons had ca 7mm dome thickness so  3mm can be milled off without problems.
Chambers 23.6cc on all 4 which I asked for when left it for porting.
(As my other K2 head and to match Billet block with its pistons)

Pistons had a strange height. Their outer flat area needed to come up so cylinder had to be milled 1mm.
Cylinder height from 85 to 84. Milled new grooves for sleeves and oil feed o-rings

Cylinder and pistons were compared to Billet block 84.5mm and its 71.25mm pistons. Get similar compression, a little bit more ok, less not. So the mechanic compared dome volumes and milled off as much as needed to get same. I guess min 2mm off, max 3mm.

It would have been better if piston height outer flat area had been flush with mating surface without base gasket with stock cylinder height 85mm.
Thin RCS base gasket + thin MLS head gasket ca 1mm squish.

[Don R]

 Yes, the F2/3 were the "hemi" heads that need a bigger bump on the pistons. Cycle X mentions using the F2 head on some of their high compression pistons to lower the ratio a little for street use in a big bore race piston.

[grcamna2]

Yes, the F2/3 were the "hemi" heads that need a bigger bump on the pistons. Cycle X mentions using the F2 head on some of their high compression pistons to lower the ratio a little for street use in a big bore race piston.

Does the F2/F3 head have the number '410' cast into it ?

[Don R]

[/quote]

Does the F2/F3 head have the number '410' cast into it ?
[/quote]
 Mine do but I've found a few heads that have no numbers or mystery numbers cast there. The F2 heads are black and have the bigger diameter valves. I've found the code on the top rear fin between the 2-3 cylinders.

[Don R]

  I got the 836 cylinder honed and cleaned up a little I also tapered the bottoms of the sleeves to help get the rings in.  The high compression pistons are RC836 by ART so they're cast. Next up is to put the rings on the pistons and slip them onto the rods, but first I need to deal with a rotated small end bushing, I made a thread in high performance about that. 

[Don R]

 The cylinder got brushed in hot soapy water, wiped down with oil and yes, there is always more grit to wash off. The rings are gapped and slid onto the pistons. Nothing broke and up is up on all of the ones marked up. Next is put the pistons back on the rods. I did taper the bottom of the jugs to help the rings compress.
 I just test dropped the cylinder over the studs and mashed a finger when it finally lined up. I wanted to check the dowels, the last guy that was in here dinged them up a bit.
  I have heavy duty studs but really dislike removing the stock ones. This will require some thought.

[Don R]

   I went for it, removing the stock studs, they came out as easy as I had hoped, not one really put up a fight.
  The heavy-duty ones are in now and the good parts that came with this bike are almost all back in this motor.
  I think Steve used many of his drag bike parts in this bitsa motor just to get the bike running again. Now it will have fresh rings and honed cylinder, all of the cam chain guide parts with the good head and RC315 cam. Re-using the RC aluminum head gasket another time probably isn't a good idea, so I'll use the generic gasket out of my parts bin. 
 

[grcamna2]

I know you're anticipating to hear it run Don. 

[Don R]

 I finally got the cylinder back on, I'm swapping to the rebuilt ported head with the 315 cam. I neglected to mark the cam gear, it's an RC with 3 sets of holes that can be flipped around for 6 different cam timings. I'll have a go at matching the numbers stamped on the end of the cam.
 I'm probably using K1 rocker stands with the oil holes drilled per Marks book. I drilled the K0 stands in my old cruizin image kitted 836 for the KH F cam.  So far so good. The next time it's opened up, it's getting an F2 cam. 

[PeWe]

An adjustable cam sprocket might be easier?
If head, cylinder are milled it will change timing.

Here my numbers on my DP315 cam when I timed it
at 0 lash and 0.04" lift
IN: Total lift: 0.368" (9,35mm)  Dur: 278,5°  open/close:35°/63,5°     LC: 104,25°   
EX: Total lift: 0.368" (9,35mm)  Dur: 282,5°   open/close:67,5°/35°    LC: 106,25°
Overlap: 70°

at running lash 0.30mm/0.30mm and 0.04" lift
IN: Total lift: 0.352" (8,95mm) Dur: 265°   open/close:28,5°/56,5°   LC:104°
EX: Total lift: 0.354" (9,0mm)  Dur: 266°   open/close: 60°/26°        LC: 107°
Overlap: 54,5°