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

[grcamna2]

  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.

Hi Don,I like the last option:street bike use,right? 

[PeWe]

They have sale according to this page if still actual.
http://www.cyclexchange.net/Engine%20Parts%20Pistons%20Page/970cc/970cc%20Pistons.htm

The flatter pistons easier to adapt to head chamber volume.
Wiseco 12.5:1 pistons might have enough meat in domes as JE (appr 7mm) so a few mm can be milled off if needed.
CR 10 something need an unmolested chamber, 22.5cc
Old ported heads got chambers opened up for the old style wider domed pistons.
It is very tempting when visiting CycleX and Dynoman.

CycleX had a new 125-70 cam for OK, price before. They have some cams, used for practical tests, still new.

Rocker arms another needed part.

[Don R]

 The 836 currently has an RC315 cam on an RC ported head. I may have that head removed to check today. The PO went to RC engineering in the 70's or early 80's, met Russ and bought these parts. I would have loved leaving it as is but wear and tear and time in the barn took a toll.

[Don R]

 It occurred to me it should be named Kodomo Nezumi or barn rat.

[PeWe]

RC parts makes it historical correct
RC ported head would be nice to look at. How it was ported etc.
Open chambers that's for sure.
My K6 got forged RC 836 pistons 1983 at a shop that sold RC and Action Fours parts. Chambers opened  for them.
Compression was good, pinging if filled gasoline at wrong gas station. Typical when twisting on 5th gear from 4000rpm, pinging just before 5000 rpm.

Chambers over 24cc when measured.
Same shop made all other typical mods that RC also did.

[newday777]

The 836 currently has an RC315 cam on an RC ported head. I may have that head removed to check today. The PO went to RC engineering in the 70's or early 80's, met Russ and bought these parts. I would have loved leaving it as is but wear and tear and time in the barn took a toll.

I bought a RC315 cam a year ago at a swap meet.

[Don R]

 This isn't the mythical RC engine the PO once owned, the head is stock, the rocker stands are two different models, early and late, one cam tower stud was a bolt, it does have the 315 cam. I'll keep these rockers on their lobes, whatever parts I end up using. The pistons are ART 65mm high compression.
  I don't see a reason why the engine was tight. The rings are all loose, and the pistons aren't scuffed. I can see a ring where #4 cylinder had a rust ring or something similar. The opposite cylinder has a vertical scratch but small.
  The cam and cam holder bearings are very clean, rockers look good.
  I imagine I could hone and ring this and it would run. That's not my plan though, I do have a ported head with springs and retainers.
  There was almost no valve lash and the cam chain was looser than it should have been. I haven't examined the cam chain tensioner yet.  These was an aluminum looking head gasket that got hung up when I pulled the head, it's junk anyway.

  I have no idea where the valve lash went, Hondaman mentioned rusty valves self polishing while running, maybe that happened. I adjusted lash with the rocker cover off and could see the cam.
  I did also re-check the cam chain tensioner and it worked when I loosened the bolt. No idea why it was loose unless I had previously tightened it with the engine at the wrong spot or wear.
 
 

[grcamna2]

The pistons and bores still look ok Don ?

[Don R]

 Not as bad as I expected. The bores show stains, but the pistons aren't scuffed like I expected. I oiled the cylinders to make it easier to turn the crank to line up the cam bolts and it spun easy after that.

 Something was making it smoke like an old 2 stroke though. It had 2 to 4% leakdown. I don't have a lot of faith in leakdown tests any more.

[Don R]

 this

[Don R]

 I was thinking about it and did not remember seeing the camchain guide, I went back out and there isn't one.
 The cam chain was sawing into the front of the block. That would explain why it didn't go 60 to 80 very well. There's no valve to piston marks so that didn't occur but it just became a total rebuild, I can't really trust anything else that was done.
 It had a lot of noise in it when it first started but went away when I fixed the clutch basket, shift problems were fixed by locktiting a new ratchet stud into place.
 This sort of blows my mind.

[grcamna2]

I was thinking about it and did not remember seeing the camchain guide, I went back out and there isn't one.
 The cam chain was sawing into the front of the block. That would explain why it didn't go 60 to 80 very well. There's no valve to piston marks so that didn't occur but it just became a total rebuild, I can't really trust anything else that was done.
 It had a lot of noise in it when it first started but went away when I fixed the clutch basket, shift problems were fixed by locktiting a new ratchet stud into place.
 This sort of blows my mind.

Full tear-down coming Don?

[Don R]

 Yes that's what I was getting at above, after this and the mixed up bolts I wouldn't expect anything else to be OK.  I dropped the sump and found what you would expect, plus some fuzzy stuff dangling off of the screen. I have options, I'm still deciding on a course of action.
  A fresh ported head came with the buy, I need to check the cc of the chambers and touch up a small ding. This motor did have great oil pressure so there is something good in there.

[grcamna2]

I see the desirable cam chain with the flat side plates;it may have had some redeeming qualities compared to the stock OEM chain with it's rounded side plates,may have had less 'dig' into your cases..
I imagine it's usable life may be near the end,having had contact with those cases. 

[BenelliSEI]

I was thinking about it and did not remember seeing the camchain guide, I went back out and there isn't one.
 The cam chain was sawing into the front of the block. That would explain why it didn't go 60 to 80 very well. There's no valve to piston marks so that didn't occur but it just became a total rebuild, I can't really trust anything else that was done.
 It had a lot of noise in it when it first started but went away when I fixed the clutch basket, shift problems were fixed by locktiting a new ratchet stud into place.
 This sort of blows my mind.

That’s brutal.

[Don R]

 I'd say it's the proverbial "toast" I wouldn't want to test it on a couple grand worth of new parts.

 Brutal is realizing it's not the RC engine he thought it was. I still got a huge deal when I bought it. In reality I could sell two or three parts and break even.

[grcamna2]

Don,does someone still sell the Tsubaki HD cam chain:the Camellia style ?

[Don R]

 I don't know, I think someone said there were old stock somewhere. Cycle X has them original and cryo treated.

[grcamna2]

I don't know, I think someone said there were old stock somewhere.

I see one on Ebay #BS25H-102L, not sure if that's the correct one;it has the rounded 'oem style' side plates..

[PeWe]

Yamiya sell DID chain of same type, they call it Yoshimura type.
Something like this
https://www.ebay.co.uk/itm/224852916705?epid=6010415333&hash=item345a4739e1:g:xOwAAOSwLi5iF0UV&amdata=enc%3AAQAHAAAA8HzrPYFpDqrZR3HUz5GoR1Nxc62RH7rwFIvH013jR60FxBVMJGireC1GQmsQUQs09Gu2bseq%2FD25x%2Fxf4N5ActCV9NHS04SCLdAQMikRoC3ZmvRRoqxbymkg%2Bo4YY7%2FumIhgMcO%2F3DOvKhTBjnBuc0XeWdLOzJkosm6ocsSH%2FgcC92CUIuXmNcl9ciy%2BN7NtWGKadEPWr3SXfmd362zX%2BVpPNCJFkI2Yuu%2FnGJR0aa3nwpzhY7X5FZHW37gO3xLzSj6l43CvWFdf7EcdDlGyp96SeVTO3SaAvb9r%2FmA%2FjUNYWJwp1g4FiunFf8CceyK7IA%3D%3D%7Ctkp%3ABk9SR5qB0JC3YQ

Is it CB350 twin pistons with those domes?

[Don R]

 I believe those are Henry Abe pistons.  When I got this one the rocker cover wasn't tightened down, I was just hoping it was an OK engine. I told the PO the cam was the RC315 and he said OK, that's the good engine.
 It had been a long time since he rode or worked on any of his Hondas, his memory was a little unclear what was what.
 He did say the turbo engine was professionally built and aside from the rusty cylinder and stuck rings it was nice inside and all there.  Both of the 836's actually are, often they aren't.
  Notice the two cam tower bolts rather than a bolt and stud.
  I noticed there is still a lot of barn stuff between the cylinder fins. I'll get that cured soon.
  It also appears the oil still has some floaties and an odd color. I was planning a rislone flush and another oil change right away to flush out the stale oil and dirt. I guess I can hand clean it all now.

[Don R]

 I'm going to Scottsdale next week to watch the rich folk buy cars at the Barrett Jackson Auction so I'm going easy on the paypal and credit card until we get back. Then the buyer picks up his new to him F1 and I have a couple thousand to spend on parts. 

[grcamna2]

Yamiya sell DID chain of same type, they call it Yoshimura type.
Something like this
https://www.ebay.co.uk/itm/224852916705?epid=6010415333&hash=item345a4739e1:g:xOwAAOSwLi5iF0UV&amdata=enc%3AAQAHAAAA8HzrPYFpDqrZR3HUz5GoR1Nxc62RH7rwFIvH013jR60FxBVMJGireC1GQmsQUQs09Gu2bseq%2FD25x%2Fxf4N5ActCV9NHS04SCLdAQMikRoC3ZmvRRoqxbymkg%2Bo4YY7%2FumIhgMcO%2F3DOvKhTBjnBuc0XeWdLOzJkosm6ocsSH%2FgcC92CUIuXmNcl9ciy%2BN7NtWGKadEPWr3SXfmd362zX%2BVpPNCJFkI2Yuu%2FnGJR0aa3nwpzhY7X5FZHW37gO3xLzSj6l43CvWFdf7EcdDlGyp96SeVTO3SaAvb9r%2FmA%2FjUNYWJwp1g4FiunFf8CceyK7IA%3D%3D%7Ctkp%3ABk9SR5qB0JC3YQ

Is it CB350 twin pistons with those domes?

'Yoshimura type' cam chain:should be the high performance item.

[Don R]

 I was considering the repercussions of a timing chain with the slack in the front. I'd think that would delay all of the cam operations, valves opening or closing after the pistons were in the correct positions, pistons pushing exhaust that can't get out.
  No wonder it said I've had enough at the stop light after running on the highway. Since it came to me stuck, I was sure I'd find stuck rings and severely damaged cylinder walls.

[Don R]

   I'm less in love with this engine now L0L, whatever else I do the cam and rockers will stay matched.  I'm thinking I'd like to get the cylinder and pistons checked just to see what the clearance is and I may look at the ring gaps.
  I was thinking, no cross hatch on the cylinders but obviously hadn't run like this before I got it. I wonder if it has been apart and just re-assembled. The rings appear to be good and loose in the grooves, I don't think they lost their temper.