Messages

31

Wanted / WANTED: Yam fork bottoming cone.

« on: August 15, 2024, 03:19:52 pm »

Hey Guy's, I was wondering if anyone might have 1 or 2 Yam DT2 fork bottoming cones, that sit on the bottom of the damping rods, I think most early Yam twostrokes, DT, RT, YZA, MXA might run the same cones, or actually any bottoming cones with a 13mm ID? Could they be posted to Central Victoria? Thanks in advance.

32

Tech Talk / Re: Yam DT1 front brake cam improvement?

« on: August 12, 2024, 08:58:44 pm »

I think I've found the issue, the elcheapo shoes don't sit central in the drum, when I lock the brake on, with the shoes in the hub, I can't slide the axle through, as I release the brake pressure, then the axle will slide through ...... hmmmm.

33

Tech Talk / Yam DT1 front brake cam improvement?

« on: August 11, 2024, 05:27:39 pm »

Hey Guy's, does anyone know of a front drum brake cam that will work in place of the stock cam on a DT1 (and just about any Yam dirtbike from '68 to '76), the actuating pad between the brake shoes has a very gentle action, causing a spongy lever action. I guess I could weld a bead of weld across my stocker but I'd rather find something that will bolt-in from another model if possible.

34

General Discussion / Re: Welcome back. Log in issues.

« on: August 10, 2024, 09:48:43 pm »

Whoo Hoo we're back !!! :-)

35

Tech Talk / Re: 1980 RM 400 fouling plugs

« on: June 13, 2024, 11:08:15 pm »

If it appears to be blowing way too much smoke (oil), maybe it has a damaged crankshaft gearbox oil seal?

36

Tech Talk / Re: 1980 RM 400 fouling plugs

« on: June 12, 2024, 11:49:10 am »

Probably not your oil/fuel mix, more the fuel/air mix :-)

37

Tech Talk / Re: Circlip on countershaft

« on: June 11, 2024, 07:00:28 pm »

If it has a nut, most surely the countershaft needs to be pulled hard to that side by the nut, so that all the gears sit in the correct position.

38

Competition / Re: Classic Weekend - Conondale QLD

« on: June 07, 2024, 09:35:28 am »

Thanks for advising, unfortunately us Victorians will have to spend the weekend in the cold

Yeh :-( But still having a ride :-)

39

Tech Talk / Re: NGK B10E & B10ES

« on: March 31, 2024, 07:30:33 pm »

Yep that makes sense, the porcelain is 2mm longer on the S.

40

Tech Talk / NGK B10E & B10ES

« on: March 29, 2024, 04:22:46 pm »

Hi Chaps, any know the difference between B10E and the B10ES ? They look the same.

41

General Discussion / Just checking in .....

« on: January 11, 2024, 10:15:44 am »

2 weeks no posts, just keeping things active :-) Come on Chaps, just talk anything VMX, I need my fix ;-)

42

General Discussion / Re: Any old boys still here ?

« on: November 17, 2023, 10:31:45 am »

I first came here in 2010, when I retired from serious roadracing, but still have connections with a few from my motocross days, from 1974 to 1986.

43

General Discussion / Re: Any old boys still here ?

« on: October 20, 2023, 09:48:31 am »

When did the forum start?

44

Tech Talk / Re: CR250M inlet port height different, why?

« on: September 09, 2023, 11:23:32 pm »

Lower ring gap

Oh that sounds boring :-(

45

Tech Talk / CR250M inlet port height different, why?

« on: September 08, 2023, 05:32:25 pm »

So here is another useless rambling post from me :-)

I've known for many years of the odd inlet port of the Honda CR250M, but I only just now wonder why? I guess I look at employing such trickery on another bike. With the top of the two inlet port windows at different heights, below is a link to the cylinder liner. I guess at a couple of the following reasons ....

* Added crankcase turbulence?

* Flow from each port directed in a different direction?

* With one port starting to close before the other, could it give a mild supercharging effect to the later closing window?

By all reports the CR250M was the fastest 250 in its time, the inlet port being the only thing that seems to stand out from the 250's, makes me wonder, hmmm.

https://www.ebay.com/itm/184383481671?hash=item2aee1ca747%3Ag%3AEcMAAOSwfs9fJG2q&fits=Year%3A1973%7CModel%3ACR250%7CMake%3AHonda

Feel free to offer your own crazy ideas :-)