Wel, I'm sad to hear about the migration of your piston (is it a seasonal migration? :P ), but good that you caught it in time :)bazmonaut wrote: Fri May 15, 2020 12:05 am First the good news: the honing operation went well. I'm calling it a success. Not as scary as I thought. Lots of oil helped by creating a 'wake' so I could adjust my in/out to match the rotation speed. Also some hand-holding from a mate.
More good news, I took Bowler's prompt and re-measured the piston to bore, and it's 0.053 which is within spec. I took three sets of measurements, at different heights and rotations on the piston and in the bore.
All good so far.
Captain Cock-up did drop in though, when I discovered that it's quite difficult to fit a 96mm piston into a 95mm bore. The piston in the pic below is actually from an SRX, which I should have known because it's stamped 1JK (which I wilfully mis-read as 1VJ... the power of the human mind). This is easily explained because I also have an SRX engine in boxes, and the pistons must have migrated between the boxes over many years and several house moves.
So, thanks Bowler for helping me avoiding awkward disappointment. The £25 rings I was so pleased to buy will stil be used, but on the SRX build and not this one. Good news is that Fowlers appear to be filling orders again so I am going to order a set of standard rings with them.
More later.
![]()
Bazmonaut's 3AJ rebuild
- Bowler
- Financial

- Posts: 152
- Joined: Sat Sep 22, 2012 3:08 pm
- What Bike or Bikes Do You Own?: -Yamaha XT600Z Ténéré '90
-Yamaha MT-09 Tracer '15 - Previously Owned Bikes: -Honda XL500S
-Honda XL500R
-Honda NX250
-Honda CB250RS
-Kawasaki GPX250R
-Kawasaki Z250C
-Moto Guzzi V35 Imola
-Jawa 350 (634)
-Yamaha XTZ750
-Yamaha SR500
-Suzuki GSX1100E(T) - Location: Zwolle, the Netherlands
Re: Bazmonaut's 3AJ rebuild
-
bazmonaut
- On the ladder

- Posts: 68
- Joined: Mon Apr 06, 2015 9:10 pm
- What Bike or Bikes Do You Own?: 3AJ Tenere
- Previously Owned Bikes: Suzuki GS250
Yamaha XT250 (twin shock 1979)
Honda VF750
Suzuki GSXR1100
Yamaha SRX600 (twin shock)
KTM Duke 640
Honda ST1100 Police - Location: Devon, UK
Re: Bazmonaut's 3AJ rebuild
These naughty parts are bed-hopping their way through my boxes I swear. Promiscuous little things.Bowler wrote: Fri May 15, 2020 7:23 am Wel, I'm sad to hear about the migration of your piston (is it a seasonal migration? :P )
But WAIT - hold my calls look what just walked in the door:

-
cadno
- Almost there

- Posts: 775
- Joined: Fri May 06, 2016 9:38 am
- What Bike or Bikes Do You Own?: lot's of Yamahas, quite a few Montesas, two BMWs a KTM and a GPZ1100
- Previously Owned Bikes: Far too many to list
- Location: Bangor UK
Re: Bazmonaut's 3AJ rebuild
from an engineering viewpoint you can feel the quality, lovely thing 
-
cadno
- Almost there

- Posts: 775
- Joined: Fri May 06, 2016 9:38 am
- What Bike or Bikes Do You Own?: lot's of Yamahas, quite a few Montesas, two BMWs a KTM and a GPZ1100
- Previously Owned Bikes: Far too many to list
- Location: Bangor UK
Re: Bazmonaut's 3AJ rebuild
I wish Wilbers shocks would breed in my garage 
-
bazmonaut
- On the ladder

- Posts: 68
- Joined: Mon Apr 06, 2015 9:10 pm
- What Bike or Bikes Do You Own?: 3AJ Tenere
- Previously Owned Bikes: Suzuki GS250
Yamaha XT250 (twin shock 1979)
Honda VF750
Suzuki GSXR1100
Yamaha SRX600 (twin shock)
KTM Duke 640
Honda ST1100 Police - Location: Devon, UK
Re: Bazmonaut's 3AJ rebuild
Is nice...
...just checking: the linkage at the bottom is the right way around isn't? The joint should be pointing forwards and not backwards right? Can't find any reference pics.


...just checking: the linkage at the bottom is the right way around isn't? The joint should be pointing forwards and not backwards right? Can't find any reference pics.


- Mezo
- Dashingly Handsome

- Posts: 6108
- Joined: Wed Mar 23, 2011 11:01 am
- What Bike or Bikes Do You Own?: Kymco agility 125 ;-)
- Previously Owned Bikes: Honda SS50, Suzuki TS50, Honda CB100, Honda CR125RZ, Yamaha YZ125, Kawasaki KX250, Suzuki TL1000S, Ducati 900SS, Ducati 900SL, a few Tenere`s.
- Location: Queensland Australia
- Contact:
Re: Bazmonaut's 3AJ rebuild
Funny that caught me out as well, it seems it would go either way right? i was back & forth wondering the same.

Mezo.

Mezo.
"A wise man makes his own decisions, an ignorant man follows public opinion"
-
bazmonaut
- On the ladder

- Posts: 68
- Joined: Mon Apr 06, 2015 9:10 pm
- What Bike or Bikes Do You Own?: 3AJ Tenere
- Previously Owned Bikes: Suzuki GS250
Yamaha XT250 (twin shock 1979)
Honda VF750
Suzuki GSXR1100
Yamaha SRX600 (twin shock)
KTM Duke 640
Honda ST1100 Police - Location: Devon, UK
Re: Bazmonaut's 3AJ rebuild
Thanks Mezo - fwoah that's a nice looking linkage! I didn't paint or plate mine cos I wanted to make progress, now wish I had as it stands out like a sore thumb...
-
cadno
- Almost there

- Posts: 775
- Joined: Fri May 06, 2016 9:38 am
- What Bike or Bikes Do You Own?: lot's of Yamahas, quite a few Montesas, two BMWs a KTM and a GPZ1100
- Previously Owned Bikes: Far too many to list
- Location: Bangor UK
Re: Bazmonaut's 3AJ rebuild
Go on, you know you have to remove it now, otherwise you'll be riding along on your otherwise mint 3AJ with that niggling thought in your head
.
-
bazmonaut
- On the ladder

- Posts: 68
- Joined: Mon Apr 06, 2015 9:10 pm
- What Bike or Bikes Do You Own?: 3AJ Tenere
- Previously Owned Bikes: Suzuki GS250
Yamaha XT250 (twin shock 1979)
Honda VF750
Suzuki GSXR1100
Yamaha SRX600 (twin shock)
KTM Duke 640
Honda ST1100 Police - Location: Devon, UK
Re: Bazmonaut's 3AJ rebuild
cadno you bastard...cadno wrote: Sun May 17, 2020 6:13 pm Go on, you know you have to remove it now ... that niggling thought in your head.
[Sighs, rolls up sleeves...]
-
cadno
- Almost there

- Posts: 775
- Joined: Fri May 06, 2016 9:38 am
- What Bike or Bikes Do You Own?: lot's of Yamahas, quite a few Montesas, two BMWs a KTM and a GPZ1100
- Previously Owned Bikes: Far too many to list
- Location: Bangor UK
Re: Bazmonaut's 3AJ rebuild
sorry fella
you know you have to.
I have a mate who struggles riding Yamaha's that aren't matching numbers, that's taking it to a different level.
you know you have to.
I have a mate who struggles riding Yamaha's that aren't matching numbers, that's taking it to a different level.
