« previous next »
Pages: [1]   Go Down

Author Topic: reusing conrod bolts  (Read 3176 times)

0 Members and 3 Guests are viewing this topic.

Offline topgun

  • Full Member
  • *
  • Posts: 43
reusing conrod bolts
« on: October 19, 2018, 12:59:29 AM »
Hi Guys I,m rebuilding a 750 with Mtc rods 900 pistons  etc what are your thoughts on using the same rod bolts I am getting conflicting opinions  on this subject I want to build this motor properly as I have invested a lot into it already as you will all appreciate Cheers Tony
Logged

Offline bear

  • Vale Bill McIntosh ......"illegitimi non carborundum"
  • Old Timer
  • ******
  • Posts: 2,575
  • Leeton in Australia
Re: reusing conrod bolts
« Reply #1 on: October 19, 2018, 02:43:05 AM »
New bolts, they should only stretch once.

Cheers,
Brian
« Last Edit: October 19, 2018, 02:52:21 AM by bear »
Logged
The older I get the faster I was.

Offline simon#42

  • Old Timer
  • ******
  • Posts: 2,586
  • liverpool
Re: reusing conrod bolts
« Reply #2 on: October 19, 2018, 09:51:34 AM »
yes new bolts .
Logged

Offline topgun

  • Full Member
  • *
  • Posts: 43
Re: reusing conrod bolts
« Reply #3 on: October 19, 2018, 11:03:09 AM »
Thanks Guys
Logged

Offline 754

  • Really Old Timer ...
  • *******
  • Posts: 29,058
Re: reusing conrod bolts
« Reply #4 on: October 19, 2018, 04:36:58 PM »
Are those answers geared to all rods , or aluminum in particular ?
Logged
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline bear

  • Vale Bill McIntosh ......"illegitimi non carborundum"
  • Old Timer
  • ******
  • Posts: 2,575
  • Leeton in Australia
Re: reusing conrod bolts
« Reply #5 on: October 19, 2018, 05:16:18 PM »
Quote from: 754 on October 19, 2018, 04:36:58 PM
Are those answers geared to all rods , or aluminum in particular ?

As far as I'm concerned conrod bolts are a consumable, same as clutch plates, piston rings, cush rubbers and the like.
So.. in my opinion, my answer is geard to all rods.
This isn't going to turn into an "oil thread" is it Frank? ;D
Logged
The older I get the faster I was.

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 15,531
  • Bike almost back to the 70's 2015
Re: reusing conrod bolts
« Reply #6 on: October 19, 2018, 11:33:34 PM »
Even Honda stock rods? I have a set of CB900 rods I might use if find a way to use the longer rods.
- These need new bolts and nuts?
Honda might have torqued them less than tuners do, like head nuts.
Logged
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline simon#42

  • Old Timer
  • ******
  • Posts: 2,586
  • liverpool
Re: reusing conrod bolts
« Reply #7 on: October 20, 2018, 04:28:50 AM »
i would always change them , there are places where you can save a bit of money and there are places where the consequences of a failed component far out weighs the price of a new one .
Logged

Offline bwaller

  • Really Old Timer ...
  • *******
  • Posts: 7,484
Re: reusing conrod bolts
« Reply #8 on: October 20, 2018, 05:21:57 AM »
Carrillo told me years ago the 1/4" Carr bolts are good for an infinite number of "torque sequences".

I agree OEM rod bolts are consumables and it makes me nervous what Carrillo told me. They talked me out of it last time I asked, However I think I'll push the issue this time. I'm certain they'll gladly sell me new bolts!  ;D
Logged

Offline MRieck

  • Really Old Timer ...
  • *******
  • Posts: 10,560
  • Big ideas....
Re: reusing conrod bolts
« Reply #9 on: October 20, 2018, 08:01:39 AM »
Quote from: bwaller on October 20, 2018, 05:21:57 AM
Carrillo told me years ago the 1/4" Carr bolts are good for an infinite number of "torque sequences".

I agree OEM rod bolts are consumables and it makes me nervous what Carrillo told me. They talked me out of it last time I asked, However I think I'll push the issue this time. I'm certain they'll gladly sell me new bolts!  ;D
Yes...the SPS bolt can be reused as long as they are not over torqued (overstretched). For what they cost they should be reusable.
Logged
Owner of the "Million Dollar CB"

Offline bear

  • Vale Bill McIntosh ......"illegitimi non carborundum"
  • Old Timer
  • ******
  • Posts: 2,575
  • Leeton in Australia
Re: reusing conrod bolts
« Reply #10 on: October 20, 2018, 08:06:59 AM »
Quote from: PeWe on October 19, 2018, 11:33:34 PM
Even Honda stock rods? I have a set of CB900 rods I might use if find a way to use the longer rods.
- These need new bolts and nuts?
Honda might have torqued them less than tuners do, like head nuts.

I wouldn't use the M3 rods Peewee. Check to make sure you have the upgraded M4's.

Cheers,
Brian
Logged
The older I get the faster I was.

Offline PeWe

  • Really Old Timer ...
  • *******
  • Posts: 15,531
  • Bike almost back to the 70's 2015
Re: reusing conrod bolts
« Reply #11 on: October 20, 2018, 10:45:33 AM »
Quote from: bear on October 20, 2018, 08:06:59 AM
Quote from: PeWe on October 19, 2018, 11:33:34 PM
Even Honda stock rods? I have a set of CB900 rods I might use if find a way to use the longer rods.
- These need new bolts and nuts?
Honda might have torqued them less than tuners do, like head nuts.

I wouldn't use the M3 rods Peewee. Check to make sure you have the upgraded M4's.

Cheers,
Brian
M3 rods.... Is that CB900 dohc 79-82?
M4 later?
I heard the CB900 rods are a little bit stronger than CB750 stock.
CB750 Stock with new F2 bolts might be OK for 836-900cc anyway. Around 80whp
Logged
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline 754

  • Really Old Timer ...
  • *******
  • Posts: 29,058
Re: reusing conrod bolts
« Reply #12 on: October 20, 2018, 12:19:23 PM »
 How about Goldenrod bolts ?
Logged
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline MRieck

  • Really Old Timer ...
  • *******
  • Posts: 10,560
  • Big ideas....
Re: reusing conrod bolts
« Reply #13 on: October 20, 2018, 08:40:14 PM »
Quote from: 754 on October 20, 2018, 12:19:23 PM
How about Goldenrod bolts ?
Some used SPS bolts...I know that for a fact.
Logged
Owner of the "Million Dollar CB"

Offline RAFster122s

  • I feel like a really really
  • Really Old Timer ...
  • *******
  • Posts: 12,293
  • SOHC4 member # 2605
Re: reusing conrod bolts
« Reply #14 on: October 21, 2018, 01:55:37 AM »
What is an SPS bolt and how do you identify it as being one?  ..no, I  didn't google it.
Logged
David- back in the desert SW!

Offline Don R

  • My Sandcast is a
  • Really Old Timer ...
  • *******
  • Posts: 19,816
  • Saver of unloved motorcycles.
Re: reusing conrod bolts
« Reply #15 on: October 21, 2018, 11:43:20 AM »
Logged
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.
Pages: [1]   Go Up
« previous next »