Small crack UT head
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Small crack UT head
03 Sep 2015 07:29
Hi! I just got my head and other parts back from glass-blasting and noiticed a small crack in the head where the valve guid in cylinder 4 on the exhaust side. Please tell me it can be fixed! Can i ignore it or can i get it wielded ?
Simon
Simon
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Re: Small crack UT head
03 Sep 2015 08:09
Looks like a new guide was installed with a piece of metal still in there. Probably won't matter as long as it doesn't go through to the lifter bore. Have you seen it and is the valve centered?
Steve
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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- zed1015
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Re: Small crack UT head
03 Sep 2015 09:22
That crack is nothing so ignore it.
AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
www.kzrider.com/forum/23-for-sale/611992...lide-mikunis?start=1
www.kzrider.com/forum/23-for-sale/611992...lide-mikunis?start=1
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- missionkz
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Re: Small crack UT head
03 Sep 2015 10:27
I think it is probably OK but, are you going to have a valve job done? Now is a perfect time so if yes, have them knock the guide out and get a better look. It a stupid simple procedure now.
Bruce
1977 KZ1000A1
2016 Triumph T120 Bonneville
Far North East Metro Denver Colorado
1977 KZ1000A1
2016 Triumph T120 Bonneville
Far North East Metro Denver Colorado
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Re: Small crack UT head
03 Sep 2015 13:08
If it hasn't been rebuilt it should be. Valve guides seals at least. They make oversize guides. Maybe that's what caused it. When I had my Honda in the early 70's,my friend who owned a shop was doing my head. I had bought valve guides but one was too loose. He put it in his lathe and knurled the outside so it would fit tight and sent me home with my finished head. That kind of know how and expertise is hard to find now.
Steve
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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Re: Small crack UT head
10 Sep 2015 07:47
Okay, thank you for your opinions ! I will send the head to a shop and get new guides and valves seats cut.
Was afraid i would have to get a new head!
Any thoughts on the oversized valve guides for the UT head ? Should i go ahead and get them or should i give the head to a proffesional and let him decide ?
Simon
Was afraid i would have to get a new head!
Any thoughts on the oversized valve guides for the UT head ? Should i go ahead and get them or should i give the head to a proffesional and let him decide ?
Simon
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Re: Small crack UT head
10 Sep 2015 09:08
He will be doing the work, he should make the call. I wouldn't accept owners parts.
Steve
Steve
Z1b1000 1975 Z1b
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
kzrider.com/forum/11-projects/598262-kz-...-will-it-live#672882
kzrider.com/forum/2-engine/597654-poser?start=240#704229
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- zed1015
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Re: Small crack UT head
10 Sep 2015 09:23 - 10 Sep 2015 09:25
The guides in your photos look like the std cast iron ones and chances are that they have never been changed.
If they need replacing then fit APE or Kibblewhite ones which are better and cheaper than OEM .
If they have been fitted correctly It's unlikely that you will need O'S guides as it takes quite a few sets to have been fitted over the years before the holes in the head become a slack fit.
If you really do need new guides I would let the mechanic that is doing the job decide what is needed.
The guides you need for the UT head are exactly the same part as those fitted to the z650,750, z900,z1000.z1100 and also Suzuki gs750,850 ,1000 and 1100.
If they need replacing then fit APE or Kibblewhite ones which are better and cheaper than OEM .
If they have been fitted correctly It's unlikely that you will need O'S guides as it takes quite a few sets to have been fitted over the years before the holes in the head become a slack fit.
If you really do need new guides I would let the mechanic that is doing the job decide what is needed.
The guides you need for the UT head are exactly the same part as those fitted to the z650,750, z900,z1000.z1100 and also Suzuki gs750,850 ,1000 and 1100.
AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
www.kzrider.com/forum/23-for-sale/611992...lide-mikunis?start=1
www.kzrider.com/forum/23-for-sale/611992...lide-mikunis?start=1
Last edit: 10 Sep 2015 09:25 by zed1015.
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