Somebody Blew It

SWest wrote:

I wouldn't 


 

Image 1


Image 2


To look at it the guide appears perfect, but those fissures start opening up with the slightest effort to flex it.  Those cracks probably run deep into the rubber material, but I hesitate to apply additional pressure to find out...just in case it may be advisable to reuse it this way.

There was no evidence of fissures like that when similarly flexing a new guide before I installed it in 2019, or again in 2022 when the top end was disassembled for head work.  That may be because the motor ran cool and was never allowed to overheat.


Guide shown below from the 84 ZN1100 engine currently under construction:
photos.app.goo.gl/zYhL3D86nTu8CJE98

Replace it ..................................

Street Fighter LTD wrote:

Replace it ..................................

 

Should the pictured guide be considered defective and/or unuseable?

daveo wrote:

Street Fighter LTD wrote:

Replace it ..................................


 

Should the pictured guide be considered defective and/or unuseable?
 

Some of my questions may be dumb or stupid, but I think this is one that begs for a good answer...

daveo wrote:

daveo wrote:

Street Fighter LTD wrote:

Replace it ..................................



 

Should the pictured guide be considered defective and/or unuseable?

 

Some of my questions may be dumb or stupid, but I think this is one that begs for a good answer...

Being it a plastic  piece which is showing signs of stress, drying out , and age 
now is the time to replace a cheap part before it causes  a expensive  failure. 
Reminds me of  a old cracked sidewall on a tire  which still has good tread.    
Risky to push it  as you know it is less than ideal to risk a blowout
Dave

daveo wrote:

daveo wrote:

Street Fighter LTD wrote:

Replace it ..................................



 

Should the pictured guide be considered defective and/or unuseable?

 

Some of my questions may be dumb or stupid, but I think this is one that begs for a good answer...

The next stage will be it will split like the one in the video. Your choice but to my mind the Cost vs Risk isn't excessive (you aren't shy with the throttle as I understand it  )

Street Fighter LTD wrote:

daveo wrote:

daveo wrote:

Street Fighter LTD wrote:

Replace it ..................................


 

Should the pictured guide be considered defective and/or unuseable?


 

Some of my questions may be dumb or stupid, but I think this is one that begs for a good answer...

 

Being it a plastic  piece which is showing signs of stress, drying out , and age 
now is the time to replace a cheap part before it causes  a expensive  failure. 
Reminds me of  a old cracked sidewall on a tire  which still has good tread.    
Risky to push it  as you know it is less than ideal to risk a blowout
Dave


 

Might it then be advisable to examine or test a previously used cam chain guide by lightly flexing it (as shown in image 2) to determine the integrity of the part, regardless how good it may appear when relaxed or unflexed (as shown in image 1)?


 

Anyone know the O.D. mm measurement of a stock 1089cc KZ, ZN, ZX, GPZ, etc 1100 cylinder sleeve?

Caliper reads 78.56mm where the sleeve exits the block, and 78mm+/- at the end.

That leaves 1.78mm wall thickness with 75mm bore...the bare minimum if I understand this correctly.

My 82 KZ1100A engine runs great with the 74mm MTC G1135-3 10.5:1 pistons (modified to 10:25:1) installed in 2019.

What difference if any should be expected with Wiseco K1172 1170 10.25:1 pistons in a fresh 84 ZN/ZX1100 motor?




 

The new shift rod seal was inserted deeper than the original which was left flush.
Installed flush creates a 1/8" space between the seal and the step shoulder behind it where oil accumulates.

Thoughts? 

I don't think that is a problem.

If there was any wear on the shift shaft, from the previous seal position, you have effectively given the new seal some "new" shaft to work on!

H.

Could someone please suggest what makes these camshafts uniquely special...





 

daveo wrote:

Could someone please suggest what makes these camshafts uniquely special...

 

 

Please pardon my interruption...

Soon I will wrestle this motor up the stairs to the garage, where the old KZ1100-A2 will be waiting.

photos.app.goo.gl/Jtm4bqPeAKyzGSSi9

You guy's won't mind me asking for further assistance...