OzVMX Forum

Marque Remarks => Yamaha => Topic started by: Shaun G on August 11, 2011, 05:52:43 pm

Title: YZ250A
Post by: Shaun G on August 11, 2011, 05:52:43 pm

A friend has got a YZ250A motor into his workshop for a rebuild. I am hoping some of you Yama-philes may be able to help with some information.

Firstly he is after a rod kit. I suggested Hot Rod's. But is there any suppliers that can be recommended.

Also the barrell does not have a cast iron sleeve. Is this normal for this model? It is apparently a one owner bike and is on the standard bore. And no it is not for sale...I checked ;D ;D ;D

Here are some pics.

(http://i648.photobucket.com/albums/uu202/STG_23/yz250a_2.jpg)

(http://i648.photobucket.com/albums/uu202/STG_23/yz250a_1.jpg)
(http://i648.photobucket.com/albums/uu202/STG_23/yz250a_3.jpg)

Any help is appreciated.

Cheers
Shaun

Title: Re: YZ250A
Post by: bazza on August 11, 2011, 06:12:33 pm

Thought the "A" had chrome barrell?

Title: Re: YZ250A
Post by: Slakewell on August 11, 2011, 06:40:03 pm

Chrome bore is standard , Love those Ti head bolts

Title: Re: YZ250A
Post by: mx250 on August 11, 2011, 06:43:41 pm

Quote from: Slakewell on August 11, 2011, 06:40:03 pm

....... Love those Ti head bolts

Anodized aluminum I'm sure ;) (I've got 4 but didn't know what they were off ::)).

Title: Re: YZ250A
Post by: Slakewell on August 11, 2011, 06:51:33 pm

The YZ A had Ti head bolts , not sure why they did as they had no other Ti bolts , and even a steel brake lever and steel axles  ???

Title: Re: YZ250A
Post by: Shaun G on August 11, 2011, 07:16:22 pm

Thanks fella's. We couldn't work out the chrome bore thing as we thought they were a later development. So the barrell needs to be re nikasilled then? Who would you recommend to do this?

And Ti head bolts are cool. I also thought they were just anodised???

And what about a rod kit?

Cheers
Shaun

Title: Re: YZ250A
Post by: ted on August 11, 2011, 08:10:09 pm

Shaun, Give Nick a call at Teknok....47322626

Title: Re: YZ250A
Post by: GMC on August 11, 2011, 09:39:24 pm

I’m led to believe the stock length rods are NLA
I’m not sure what models they come from but I believe you can use a later model longer rod kit and a later model piston with a lower deck height so you won’t need to use a spacer under the barrel.

Title: Re: YZ250A
Post by: Freakshow on August 12, 2011, 02:04:07 am

aluminum anodised.
Yes rods are still available
yes other rods that fit are available, pins over the counter, mains over the counter, washer, small end bearing and gugeon etc too
 yes pistons are but your better of sleeving it then you can have as many oversizes as you like as you wont find the chrome rings anymore there is no reason to save the old chrome liner.
otherway round Geoff you use a lower rod and a normal piston from 74-79 even wiseco and woosner make them for this application

Tell the guy to call me if he wants and ill take him through his options.  there are some easy ways to do this and some hard ways.

Title: Re: YZ250A
Post by: Shaun G on August 12, 2011, 07:53:12 am

Thanks for the info everyone. I have passed it on to my mate.
Cheers
Shaun