OzVMX Forum

Marque Remarks => Yamaha => Topic started by: E74 on June 06, 2008, 06:48:43 pm

Title: YZ125L
Post by: E74 on June 06, 2008, 06:48:43 pm
My life long mate Bruce the Goose and extrodinary Digeridoo player has Just bought a very low hr YZ25L which we are currently restoring, Bruce raced MX from the late 70's through to the thumper nats and Amcross series but hasn't raced for some time now, He has been through a tough time as late ( on a personal level) and my reintroduction to him of the fun that could be had on a motorcycle was realised at the recent Rockley Vinduro where he rode one of my bikes, here is a shot of where his project begins , we intend to have it on the track by June 22 at Port Kembla at the Heaven MX Meeting.

(http://i113.photobucket.com/albums/n208/hemiy09/005-1.jpg)
Title: Re: YZ125L
Post by: Nathan S on June 06, 2008, 08:25:57 pm
They're good bikes, just watch the power valve. The two halves come loose and then fall into the piston, and/or they jam with carbon and then shear the drive segment on the PV drum.

And Yamaha road bike parts (which are reliable) don't fit.

All the tests of the day complained about a lack of top-end power, but apparently the fix is pretty easy.
Title: Re: YZ125L
Post by: E74 on June 06, 2008, 08:32:51 pm
Ah Huh, any one know the fix?,

I have just pulled down the top end so I think I will dismantle the powervalve for a clean up and lube, found the strangest thing though, this motor has NEVER been apart but has blue heat marks on the crank balancers right near the big end, is this common or represent a problem?


(http://i113.photobucket.com/albums/n208/hemiy09/003-3.jpg)
Title: Re: YZ125L
Post by: Nathan S on June 06, 2008, 08:47:57 pm
The gumming-shearing problem is easily avoided by not neglecting the bike (ie: check and clean it semi-regularly).
The loose bolt thing can be kept on top of simply by checking/tightening it regularly - between race meets should be plenty. There's also the possibility of using some sort of temp-resistant Loctite, but I'm yet to try it myself (I've been too busy sulking over it blowing up to spend the money fixing it....).
Title: Re: YZ125L
Post by: E74 on June 13, 2008, 09:15:30 pm
Amazing what a difference a week can make!

(http://i113.photobucket.com/albums/n208/hemiy09/005-2.jpg)

(http://i113.photobucket.com/albums/n208/hemiy09/002.jpg)
Title: Re: YZ125L
Post by: yzhilly on June 13, 2008, 09:37:06 pm
Very nice i wish i could get my 125K moving that fast ,  What did you do with the Alloy parts ??? they all look like new
Title: Re: YZ125L
Post by: E74 on June 13, 2008, 09:52:23 pm
Scotchbrite!, you can get 3 grades of it at any Auto store, then rub like buggery!! the lower fork legs and lower tripple clamp also got a coat of POR 15 Glisten PC Clear, Carby was cleaned with that fandangled Yamaha carby cleaner. I do all the Zinc plating myself with a home plating kit.
Title: Re: YZ125L
Post by: Lozza on June 15, 2008, 08:42:30 pm
That blueing is from one thing HEAT.I would be treating that to a crank rebuild before I gave it a flogging.There doesn't look to be anywhere near enough side clearence on the big end which would account for the excess heat.
Title: Re: YZ125L
Post by: paul on June 15, 2008, 08:53:10 pm
WHATS THE CARB CLEANER CALLED
Title: Re: YZ125L
Post by: caps 999 on June 15, 2008, 08:59:00 pm
what foot pegs are you using
Title: Re: YZ125L
Post by: E74 on June 16, 2008, 09:33:12 pm
WHATS THE CARB CLEANER CALLED


 Yamaha Carburetor Cleaner Dip

(http://i113.photobucket.com/albums/n208/hemiy09/carbclean.jpg)
Title: Re: YZ125L
Post by: E74 on June 16, 2008, 09:34:00 pm
what foot pegs are you using

X-Treme YZ
Title: Re: YZ125L
Post by: E74 on June 18, 2008, 08:56:40 pm
a little progress

(http://i113.photobucket.com/albums/n208/hemiy09/002-1.jpg)
Title: Re: YZ125L
Post by: Billet YZ on July 27, 2008, 01:21:06 pm
Any chance of an update E74 ??  Would be great to see this bike when it`s finished. Thanks Peter.
Title: Re: YZ125L
Post by: E74 on July 27, 2008, 01:46:56 pm
A NOS front rim has been holding the whole project up, just obtained one and I am hoping to build the wheels tonight, a new Clarke tank has been ordered from the states and I expect it this week, It will be finnished within a fortnight, I will post it up as soon as its done....
Title: Re: YZ125L
Post by: YSS on July 27, 2008, 03:00:16 pm
Is that going to be your first wheel on the new jig?
Title: Re: YZ125L
Post by: E74 on July 27, 2008, 04:11:33 pm
Is that going to be your first wheel on the new jig?


Nope, the YZ125L wheels will be the 7th and 8th wheels to go onto the Jig.. ;D ;D ;D ;D ;D ;D
Title: Re: YZ125L
Post by: YSS on July 27, 2008, 04:25:09 pm
I told you , replacing spokes is not that hard . After a few you get the hang of it. So the jig has more than paid for it self . I am glad.
Title: Re: YZ125L
Post by: YSS on July 27, 2008, 04:35:12 pm
This the maschine I built for Link . With that you can also build offset wheels and drill rims .
Les from Mainly Maico is getting an updated version shortly.