Messages

1

Wanted / 84 YZ490 frame

« on: June 02, 2020, 07:16:45 pm »

Hi all,

Just letting you guys know out there that i'm searching a good reasonable used 84 YZ490 frame.

Damages such as minor cracks and chipped paint are acceptable as long as none of the mounting brackets are missing.

Feel free to PM me or leave a comment below if you happen to have a spare one and have no use of. We can always work out a good price

Jack.   

2

Tech Talk / Re: Mikuni Power Jet adjustment

« on: May 24, 2020, 02:31:15 pm »

I was told the same thing by a former dealer mechanic that i was working with during my high school years...for every single bike that i own now i always start with the biggest jet size possible and expect it to sputter then go down from there....It's the first time for me to try the power jet out though. Bought the kit a few years ago and never got around to use it until recently when i discovered a brand new TM38 in my file cabinet so might as well i will replace my VM36 roundslide with it.

I assume that the main jet is still the primary jet to be changed at 3/4 to WOT circuit with the power jet but when should i be changing the size of the power jet if necessary?

3

Tech Talk / Mikuni Power Jet adjustment

« on: May 24, 2020, 11:01:33 am »

Hello all,

I have a Mikuni power jet kit installed on my TM38 flatslide carb and Mikuni recommends that original main jet should be reduced by 25% and the reduction will become the size of the power jet.

So in my case my bike is currently using a #380 main jet so i trimmed it back by 25% which now #95 will become the size of the power jet however this is a conversion from VM36 roundslide to TM flatslide with power jet kit so i started off in a richer side by installing a #320 main and a 97.5 power jet then go from there..

If the engine ever shows a rich/lean symptom which most likely it's gonna happen..should i be making the adjustment on the main jet first and leave the power jet alone until i have find a suitable main jet for it or should i be making changes on both simultaneously using the aforementioned Mikuni's formula? and for the future changing condition, should i only make changes on the main jet, power jet or both?

Best Regards,
Jack   

4

Tech Talk / Re: Steering stem nut torquing?

« on: January 01, 2020, 08:23:22 pm »

It's all sorted i only spin the nut until all the free play is gone then zap the big nut up a few times and it's now perfect. Just have to bring her out now for a few laps for it to seat in and further adjust it. Thanks everyone for the help and ideas 

5

Tech Talk / Re: Steering stem nut torquing?

« on: December 26, 2019, 07:23:49 am »

Yes indeed, i don't know why would Yamaha call for such amount of torque for the big fixing nut. I've never have this happened before and it's straightforward standard headstock so i'm going to clean up the threads and replace the nuts with the spares i have and let's see how it turns out.

6

Tech Talk / Re: Steering stem nut torquing?

« on: December 25, 2019, 04:20:10 pm »

Yes the pinch bolts on both sides are loosened before i tighten the big nut up. Mine is a IT250K and i have a factory service manual right in front of me now. It clearly stated that it should be torque down to 94 ft.lb which i do think it's a bit too much as well. I have a 01 YZ250F here and in the factory manual yamaha recommended the big nut torque at 105 ft.lbs which it's unbelievable.

7

Tech Talk / Re: Steering stem nut torquing?

« on: December 19, 2019, 05:32:33 pm »

I tried tighten the stem nut without even putting any preload on the bearing with the ring nut. For whatever reason it's pulling everything together when i reach the torque specification on the torque wrench. I also looked on the diagram to make sure i'm not missing any parts and it's all there in the right order.

8

Tech Talk / Steering stem nut torquing?

« on: December 19, 2019, 04:22:42 pm »

Hello all,

I'm having a bit of trouble on tightening the 27mm steering stem nut on my Yamaha IT250. I've adjusted the ring nut at the bottom to eliminate the free play and minimize the binding perfectly however when i was trying to tighten up the big stem nut on top to the specified torque of 94 ft.lbs with a torque wrench, it seems to be binding the entire assembly up after tightening. Anyone know what's going on here?

Jack.

9

Tech Talk / Re: Yamaha twin leading front brake adjustment?

« on: October 21, 2019, 05:37:50 pm »

Tried you method plus my little idea of measuring the gap between the brake cam and the cam contact surface of the shoes. It's all sorted now and waiting for a new set of brake shoes while i have it apart. Thanks for your help

10

Tech Talk / Yamaha twin leading front brake adjustment?

« on: October 20, 2019, 08:01:54 am »

G'day folks,

This is my first time ever to work on a twin leading from brake and the factory service manual stated that the brake arm should be installed with the brakes applied. What would be the trick to install and adjust these TLS?

Cheers,
Jack

11

Wanted / 1982 YZ250J expansion chamber

« on: June 22, 2019, 08:56:47 pm »

G'day guys,

I'm after an OEM expansion chamber in reasonable condition for my 1982 YZ250J. Please let me know if you have one for sale to clear up your garage/shed spaces.

Thanks,
Jacky.

12

Wanted / Re: 1984 YZ490 Frame

« on: February 22, 2019, 10:36:06 pm »

When i got the frame for my IT250K it was pretty rusty however once it's sand blasted it was mainly surface rust with only little pin holes which i got away with some good quality fibreglass filler....Definitely one thing to keep in mind but these days frames are hard to come by so i sort of take the first one that comes..and of course with plenty of photos beforehand. For the YZ490 frame, i would rather be focusing at the brackets/supports of the frame..these frames are well known to have either bent or broken brackets and often it leads to the crack on the frame tubes. It's one of the main reason why i want to replace mine since it came with a lot of defects when i purchased it. 

13

Wanted / 1984 YZ490 Frame

« on: February 21, 2019, 07:39:26 pm »

Hi all,

I'm after a 1984 YZ490 frame in reasonable condition. A bit of rust and scuffs should be fine. Please let me know.

Thanks,
Jacky

14

Tech Talk / Wiring loom re-wrapping?

« on: November 30, 2018, 06:57:49 pm »

G'day all,

I've recently purchased an Aus spec wiring loom for my IT250K.....it was looking a bit dodgy so i decided to replace all terminals and tidy up the wires by unwrapping it all...now it's all sorted and i'm ready to wrap it back up together...don't really wanna use electrical tape as they go gooey and comes off over time. What other options are you guys using apart from the electrical tape?

15

Tech Talk / Re: Jumping on 2nd gear??

« on: October 29, 2018, 10:46:38 pm »

It seems to make sense for the dodgy dogs...i will just have to take it apart again for further inspection and keep you guys updated...thanks for everyone's help much appreciate it