'79' shafty with a lot of vibration
- Greg Davis
- Topic Author
- Offline
- User
- Posts: 6
- Thanks: 0
'79' shafty with a lot of vibration
23 Jul 2020 12:13
Hi All, I'm new here but am a member of Kz1300.com. I recently purchased an "79' 1000st to have a rider while working on the 1300'
My question is the 1000 seems to have an unusual amount of vibration, reminding me of my old h1 500 it is strong enough to numb my hands
after a 30 min. ride. What could be causing this? any help would be appreciated. Thanks Greg
My question is the 1000 seems to have an unusual amount of vibration, reminding me of my old h1 500 it is strong enough to numb my hands
after a 30 min. ride. What could be causing this? any help would be appreciated. Thanks Greg
Please Log in or Create an account to join the conversation.
- Nessism
- Offline
- Sustaining Member
- Posts: 7529
- Thanks: 2887
Re: '79' shafty with a lot of vibration
23 Jul 2020 16:14
Twisted crank?
Ed
Carb O-ring Kits : www.kzrider.com/forum/3-carburetor/61807...-o-ring-kits?start=0
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
Carb O-ring Kits : www.kzrider.com/forum/3-carburetor/61807...-o-ring-kits?start=0
www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know
1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
The following user(s) said Thank You: Greg Davis
Please Log in or Create an account to join the conversation.
- Greg Davis
- Topic Author
- Offline
- User
- Posts: 6
- Thanks: 0
Re: '79' shafty with a lot of vibration
24 Jul 2020 10:50
Assuming it is a twisted crank how would one go about checking for this? Require a tear down or can be done with indicator from the ends of crank or measure
pistons 1-4 at top dead center {just guessing on that one) I have a full machine shop, so not afraid of attempting much but would rather not tear it down
unless needed.
pistons 1-4 at top dead center {just guessing on that one) I have a full machine shop, so not afraid of attempting much but would rather not tear it down
unless needed.
Please Log in or Create an account to join the conversation.
- krazee1
- Offline
- User
- Posts: 360
- Thanks: 199
Re: '79' shafty with a lot of vibration
24 Jul 2020 13:26
Verifying that cylinders 1&4 are at TDC at the same time, and then the same check for 2&3 would eliminate a twisted crank as the cause of your vibration. Could be accomplished with a TDC finder or dial indicator through the spark plug hole along with a pointer or degree wheel. Unless your bike was subjected to full throttle starts with a sticky tire, a twisted crank on a 79 model would be unusual/unlucky. I think the twisted crank thing became more prevalent in the early 80s with the J motors. I did have a buddy that twisted the crank on a 1982 CSR1000, the result of drag racing. Have you checked to be sure your motor mounts are tight?
Mike
Mike
Former M.E. at Kawasaki Motors Manufacturing, Lincoln, NE
1966 W1 (the Z1 of 1966-50H.P. and 100mph!)
1974 Z1
1978 KZ1000 LTD
1976 KZ900B pile O parts
1980 KZ750E
1980 Honda XL250S (I know, wrong flavor!)
1966 W1 (the Z1 of 1966-50H.P. and 100mph!)
1974 Z1
1978 KZ1000 LTD
1976 KZ900B pile O parts
1980 KZ750E
1980 Honda XL250S (I know, wrong flavor!)
The following user(s) said Thank You: Greg Davis
Please Log in or Create an account to join the conversation.
- ghostdive
- Offline
- User
- Posts: 390
- Thanks: 118
Re: '79' shafty with a lot of vibration
24 Jul 2020 16:01
More details would help narrow it down; my 750 shaft was vibrating a TON before I balanced my carbs. It also may be that your timing is off!
Does it vibrate at a particular speed or RPM range?
Does it vibrate at a particular speed or RPM range?
1982 KZ750 Spectre - 6 speed swap, BS34s, 18" rear wheel
2001 ZX-6R
2001 ZX-6R
The following user(s) said Thank You: Greg Davis
Please Log in or Create an account to join the conversation.
- hardrockminer
- Offline
- Sustaining Member
- Posts: 2991
- Thanks: 1090
Re: '79' shafty with a lot of vibration
24 Jul 2020 16:51
I was thinking the same thing as ghost dive.
I have several restored bikes along with a 2006 Goldwing with a sidecar. My wife has a 2019 Suzuki DR 650 for on and off road.
The following user(s) said Thank You: Greg Davis
Please Log in or Create an account to join the conversation.