ADVrider

Go Back   ADVrider > Bikes > Old's Cool > Airheads
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 03-15-2008, 10:12 PM   #61
Lornce OP
Lost In Place
 
Lornce's Avatar
 
Joined: Aug 2003
Location: Way Out There.
Oddometer: 17,403
Interesting to note the difference between the stocker on the left and the Andrews cam on the right.

The Andrews is a higher lift, shorter duration cam designed to improve mid-range which is where this motor will spend the majority of it's time.

Stock cam at 240k kms was in perfect condition, btw. Show me another air-cooled motorcycle engine design that originated in '69 that can produce a cam looking like that at 240k kms?

Honda 750K, you say? Fahggeddaboud'dit.



Lornce screwed with this post 08-25-2010 at 10:53 PM
Lornce is online now   Reply With Quote
Old 03-15-2008, 10:16 PM   #62
Lornce OP
Lost In Place
 
Lornce's Avatar
 
Joined: Aug 2003
Location: Way Out There.
Oddometer: 17,403
For a motor that was severely overheated, muddy oil contaminated and maybe even oil starved... the pistons look remarkably good.



Lornce screwed with this post 08-25-2010 at 10:53 PM
Lornce is online now   Reply With Quote
Old 03-15-2008, 10:19 PM   #63
Lornce OP
Lost In Place
 
Lornce's Avatar
 
Joined: Aug 2003
Location: Way Out There.
Oddometer: 17,403
Squish band might be a little tight, though. Carbon doesn't seem to get much of a chance to find a home.

Either that or it's just working so efficiently it "swirls away". Hah hah hah...

That's a joke, son.



Lornce screwed with this post 08-25-2010 at 10:54 PM
Lornce is online now   Reply With Quote
Old 03-15-2008, 10:23 PM   #64
Lornce OP
Lost In Place
 
Lornce's Avatar
 
Joined: Aug 2003
Location: Way Out There.
Oddometer: 17,403
Bores look pretty good, too. Not at all the mess I thought I was going to find.

Hmmmn....






Lornce screwed with this post 08-25-2010 at 10:55 PM
Lornce is online now   Reply With Quote
Old 03-15-2008, 10:44 PM   #65
Lornce OP
Lost In Place
 
Lornce's Avatar
 
Joined: Aug 2003
Location: Way Out There.
Oddometer: 17,403
Now the rings are telling me a couple of interesting stories...

First: I'm going to have to dig around to refresh my memory on the ideal end gap, but I'm thinking 0.003" - 0.004"/bore inch should be spec for these rings.

Which tells me these are severely worn showing 0.027" at the major thrust point of the bore. Orta be closer to 0.012" - 0.016", *I think*. (famous last words).

Secondly: Measureing the ring end gap at the unworn portion at the bottom of the bore and then again at the major thrust point about an inch below the top of the bore reveals a ring end gap difference from 0.0235" to 0.027", or 0.0035".

If we devide 0.0035" by pi we learn the bores have a tiny bit more than 0.001" of taper.

Translation: Who cares? That's not enough to worry about. Though I do have a fresh set of barrels that were cut for these 1050 pistons at the same time as the set that's in use.

Why? Because pistons don't usually wear very much. It's the rings and iron bores that do most of the wearing.

ie: New rings and the the fresh cyls and these pistons could go back to work at practically new spec. But for 0.0011" taper, I'm not done with the old ones yet.



Lornce screwed with this post 08-25-2010 at 10:55 PM
Lornce is online now   Reply With Quote
Old 03-16-2008, 06:27 AM   #66
datchew
Don't buy from Brad
 
datchew's Avatar
 
Joined: Aug 2005
Location: Savannah - the dirty south
Oddometer: 7,408
Quote:
Originally Posted by Lornce
I like to start an engine re&re with a messy bench.

Never trust a clean bench.
I bet Stagehand cleans his bench first.


You need some new feeler gauges Lornce.
datchew is offline   Reply With Quote
Old 03-16-2008, 06:30 AM   #67
Stagehand
+/- V TDSPP
 
Stagehand's Avatar
 
Joined: Oct 2004
Location: Shawangunks
Oddometer: 24,997
Quote:
Originally Posted by datchew
I bet Stagehand cleans his bench first.
When I can find it
__________________
Unintentional psychokinesis.
Stagehand is offline   Reply With Quote
Old 03-16-2008, 06:49 AM   #68
Lornce OP
Lost In Place
 
Lornce's Avatar
 
Joined: Aug 2003
Location: Way Out There.
Oddometer: 17,403
Those are my favourite feeler guages. Can't find them like that anymore. Lost the 0.0015" a few years ago when I loaned them to a workmate.


Here's a good shot of the relief or "counter bore" in the case that Anton was talking about in Notrex's thread. If you can imagine the corresponding shape on the base of the cylinder spigot, you'll understand what he needs to turn down before he can fit the nikasil cylinder to the earlier case which has no relief or "counter bore" segment.



Lornce screwed with this post 08-25-2010 at 10:56 PM
Lornce is online now   Reply With Quote
Old 03-16-2008, 08:26 PM   #69
datchew
Don't buy from Brad
 
datchew's Avatar
 
Joined: Aug 2005
Location: Savannah - the dirty south
Oddometer: 7,408
Keep going Lornce. Always like the tidbits you happen to call attention to.
datchew is offline   Reply With Quote
Old 03-17-2008, 01:06 PM   #70
Rapid Dog
bikes, booze, broads...
 
Rapid Dog's Avatar
 
Joined: Oct 2003
Location: Strangel Living West of Hell
Oddometer: 8,965
Thumb Cammies

...I have the Rennsport cam in my '91...I really really like the mid-range on this bike!
__________________
'09 450 EXC Nani Roma Limited/'08 R1200R-Gone to the Hipsters/'02 Dirty lil KTM400EXC-gone to a good home/'10 WR290X/R buhbye!
'81 R100RS Rattlecandy Red/'06 950 ADV Orangeboom/91 R100GSPD Derelict

Rapid Dog is offline   Reply With Quote
Old 03-17-2008, 04:26 PM   #71
Lornce OP
Lost In Place
 
Lornce's Avatar
 
Joined: Aug 2003
Location: Way Out There.
Oddometer: 17,403
Quote:
Originally Posted by Rapid Dog
...I have the Rennsport cam in my '91...I really really like the mid-range on this bike!

Who/what is a Rennsport Cam, RDog?

Is that the latest parlance for the old BMW 336 degree cam?
Lornce is online now   Reply With Quote
Old 05-11-2008, 07:42 PM   #72
Lornce OP
Lost In Place
 
Lornce's Avatar
 
Joined: Aug 2003
Location: Way Out There.
Oddometer: 17,403
A pair of Jesse bags arrived in the mail the other day and reminded me I've still got a GS/PD disemboweled in the basement.

Stay tuned, things are gonna start happening around here.




Someone loan Flug an airhead until he figures it out.

Lornce is online now   Reply With Quote
Old 05-11-2008, 08:45 PM   #73
datchew
Don't buy from Brad
 
datchew's Avatar
 
Joined: Aug 2005
Location: Savannah - the dirty south
Oddometer: 7,408
Quote:
Originally Posted by Lornce
A pair of Jesse bags arrived in the mail the other day and reminded me I've still got a GS/PD disemboweled in the basement.

Stay tuned, things are gonna start happening around here.
Been wondering what happened to you.
datchew is offline   Reply With Quote
Old 05-12-2008, 03:36 PM   #74
Lornce OP
Lost In Place
 
Lornce's Avatar
 
Joined: Aug 2003
Location: Way Out There.
Oddometer: 17,403
Quote:
Originally Posted by datchew
Been wondering what happened to you.
Oh, I got sidetracked riding the Buell and prepping the R50/5 for sale and riding the R50/5 and regretting selling it and... You know how it can be.





Lornce screwed with this post 08-25-2010 at 10:58 PM
Lornce is online now   Reply With Quote
Old 05-13-2008, 11:26 AM   #75
Rapid Dog
bikes, booze, broads...
 
Rapid Dog's Avatar
 
Joined: Oct 2003
Location: Strangel Living West of Hell
Oddometer: 8,965
Thumb

Quote:
Originally Posted by Lornce
Who/what is a Rennsport Cam, RDog?

Is that the latest parlance for the old BMW 336 degree cam?
Not sure about this, guy I bought it from used the word Rennsport. That said I did check the number but I don't recall, but I think it was a 336 stamped on the end.
Snowbum briefly talks about it hear: Mods.

At any rate, my bike kicks in at about 4Krpm like no other airhead I ever rode. It's a real blast to ride.
__________________
'09 450 EXC Nani Roma Limited/'08 R1200R-Gone to the Hipsters/'02 Dirty lil KTM400EXC-gone to a good home/'10 WR290X/R buhbye!
'81 R100RS Rattlecandy Red/'06 950 ADV Orangeboom/91 R100GSPD Derelict

Rapid Dog is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

Forum Jump


Times are GMT -7.   It's 09:10 AM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014