Author Topic: worst nightmare--need cb400f cylinders! Help!  (Read 10198 times)

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Offline Really?

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I don't have a motorcycle, sold it ('85 Yamaha Venture Royale).  Haven't had a CB750 for over 40 years.

The Wife's Bike - 750K5
The Kid's Bike - 750K3

Offline jessezm

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #26 on: October 01, 2011, 08:15:37 AM »
I was going recommend Advanced Sleeve.  I just got a sleeve made by them for the YZ. Excellent!

Well, I got a block on the way from a fellow member, so I should be back in business soon!

Offline Really?

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #27 on: October 02, 2011, 08:56:48 PM »
Glad to hear you have something going!
I don't have a motorcycle, sold it ('85 Yamaha Venture Royale).  Haven't had a CB750 for over 40 years.

The Wife's Bike - 750K5
The Kid's Bike - 750K3

Offline jessezm

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #28 on: October 03, 2011, 06:24:16 AM »
Glad to hear you have something going!

Ain't gonna let no stinkin' gouged up cylinder keep me down!

Offline crazypj

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #29 on: October 03, 2011, 06:46:47 AM »
If you change sleeves, shrink them in before pressing. Make an alloy plug about 0.010 smaller than bore diameter
Honda use a pretty low interference fit (0.001~2" instead of more usual 0.004")
I fake being smart pretty good
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Offline jessezm

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #30 on: October 03, 2011, 07:08:27 AM »
If you change sleeves, shrink them in before pressing. Make an alloy plug about 0.010 smaller than bore diameter
Honda use a pretty low interference fit (0.001~2" instead of more usual 0.004")

Can you explain what you mean a little more?  I'm just not familiar.  I was going to take it to a local machine shop to have them pressed in, but I want to know what to tell them about the tolerances, etc.  Thanks!

Offline 754

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #31 on: October 03, 2011, 08:03:42 AM »
Maybe a member could send you a spare GF they are not using, then everything is fixed...................................................jk
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Offline jessezm

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #32 on: October 03, 2011, 10:36:36 AM »
Maybe a member could send you a spare GF they are not using, then everything is fixed...................................................jk

ahah!  then all my problems would go away!  or multiply?

Offline Really?

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #33 on: October 03, 2011, 10:43:28 AM »
Prolly multiply.
I don't have a motorcycle, sold it ('85 Yamaha Venture Royale).  Haven't had a CB750 for over 40 years.

The Wife's Bike - 750K5
The Kid's Bike - 750K3

Offline crazypj

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #34 on: October 04, 2011, 09:59:27 AM »
If you change sleeves, shrink them in before pressing. Make an alloy plug about 0.010 smaller than bore diameter
Honda use a pretty low interference fit (0.001~2" instead of more usual 0.004")

Can you explain what you mean a little more?  I'm just not familiar.  I was going to take it to a local machine shop to have them pressed in, but I want to know what to tell them about the tolerances, etc.  Thanks!
Just pressing them cold can damage the block.
 It probably won't be bad but may distort liner if it binds anywhere
 If you shrink them in place first, they only have to move about 0.010" so you don't get the same damage (if any)
I fake being smart pretty good
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Offline jessezm

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #35 on: October 04, 2011, 10:08:21 AM »
I'm sorry, I just haven't done this before so I'm trying to understand exactly what you mean--by shrink them in place, do you mean putting them in the freezer first, and then pressing them in?  Do you heat the block as well?  Sorry, for the dumb questions...

And by "they only have to move about 0.010", I'm not not sure I can picture what you mean either.

Offline crazypj

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #36 on: October 05, 2011, 07:32:54 PM »
You got the old sleeves out OK?
Heat block without sleeves, (no need to freeze them)
Slide them into heated block. (make sure you have some wood blocks ready to stand it on)
 Slide them into position (don't drop them in can crack flange)
 When everything has cooled down, you'll probably find flanges are sticking out slightly.
 Some people machine top of block flat, you may need to but only AFTER you check they are all the way in.
So, you press them after shrinking into place then, machine if necessary
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Offline Powderman

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #37 on: May 04, 2013, 12:34:21 PM »
I know this is an old thread but I am nearing a sleeve bore for a 466 kit soon. I notice people talking about the sleeves in the block. I may seem stupid and I am when it comes to wrenching on these old fours, but aren't the sleeves in the cylinders and not in the block or do I have my definitions wrong? When putting the cylinders onto the pistons do 2 go into the cylinder at the same time or are they staggered? Do you need 2 ring compressors? Boy, talk about noob questions. ::)

Offline MoMo

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #38 on: May 04, 2013, 12:38:28 PM »
You do two pistons at a time and will probably need ring compressors due to the lack of cylinder chamfer when the cylinders are bored...Larry

Offline Powderman

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #39 on: May 04, 2013, 01:03:58 PM »
Can the chamfer be put back in or is there not enough meat left in the sleeve to safely do so?

Offline Tim2005

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #40 on: May 04, 2013, 01:28:48 PM »
There's not enough meat left to create a new chamfer, unfortunately.  Fitting them is one job I really try to avoid on my 460, getting the whole motor out and onto the bench helps a little, but it's still very awkward.

If you've not done many motors before (or even if you have) you'll probably find it's cheaper paying a pro to do it than buying all the replacement rings for the ones that you break if you try yourself!

Have you bought one of the ebay Cruzinimage kits? They are meant to be good.

Offline Powderman

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #41 on: May 04, 2013, 07:15:54 PM »
There's not enough meat left to create a new chamfer, unfortunately.  Fitting them is one job I really try to avoid on my 460, getting the whole motor out and onto the bench helps a little, but it's still very awkward.

If you've not done many motors before (or even if you have) you'll probably find it's cheaper paying a pro to do it than buying all the replacement rings for the ones that you break if you try yourself!

Have you bought one of the ebay Cruzinimage kits? They are meant to be good.
I have not bought one yet. There are 2 sellers on ebay with them. One is Cruzin who has it for $110/22.50 shipping ($132.50) and 4into1.com has the same one (they claim) for $132.38/free shipping which makes it $.12 cheaper and shipped from the states. 4into1 has it on their website for $100 even, now I just need to negotiate a good ship price.

Offline crazypj

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Re: worst nightmare--need cb400f cylinders! Help!
« Reply #42 on: May 04, 2013, 09:37:30 PM »
The liners are the cylinders.
Pistons run in cylinders, liners fit in block to hold the cylinders in place and provide cooling through fins
I fake being smart pretty good
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