I used original Yamaha parts for that.

This is what cost me in €, including cam chain. Yes its more expensive, but not that much. 2012 Spanish prices without VAT. Shouldnt differ too much for you, I guess.

http://i1097.photobucket.com/albums/g346/pvonramu/motorTenere/costegaskets-1.jpg ...

I am using Wirth front springs with SAE15 oil (builder recommends 10). Works really well. At first I thought to change it back to 10, but now I wouldn't. It might be too reactive in slower, trickier parts, but the faster you ride, the better it works (offroad). At rally pace it's great.

Stock right ...

I guess I shouldn't be surprised, as Spain is the home of OSSA, MONTESA, and BULTACO! :rock:


I'm a big OSSA fan. My uncle raced a OSSA in the 60's.

They are building some very nice bikes :drool:

twin injector EFI 2 stroke 300cc. And look at the expansion chamber under the seat, the tank ...

Hey Cucumber, that is interesting! How did you end up there?


Awesome report. I have been to Spain but I never saw country-side like this. :shades:

Makes me want to grab a bike a go for a ride over there.

I guess I shouldn't be surprised, as Spain is the home of OSSA, MONTESA, and BULTACO ...

Few words and more photos of the ride 2 weeks ago to the Mestrazgo region, in east-central Spain.

Our basecamp was the hotel Villa de Estercuel, in a small village. The people is nice (one of the owners is a riding buddy).
http://www.villaestercuel.com/


I met in Estercuel to ride some trails ...

Sure, tanks and bashplate water tank are original.

It's only my impression. Basically there's only one pic, so it is difficult to say one thing or the other.

Having seen another YMF Marathon 660, I'm not sure this is a real Marathon or a normal 660 with the big fuel tanks.

The Marathon is not just a standard bike with different tank and rear shock. There are many other small bits that make them different and special.

the 640 tank would be nice also. And there are plenty of ktm parts around + also new parts are cheap.

How deep do you want to go in this build? Will you cut the rear frame? A guy in the spanish forum did it, then bolted an aluminium subframe from an enduro bike (a ktm again). Also fitted longer ...

I have allways thought about changing the fuel tank. Wether for a bigger one (from the XTZ600) or a lighter, plastic one made for enduros (acerbis big tanks).

Never tried.


This italian guy did some phantastic transformation to his 660. I have never seen any other video nor photo of the bike ...

I had not seen this! :omg:

Great post, very nice mods and phantastic trip and pictures of it. :drool:


What's your opinion on the rear Mitas in sand? Is that the Dakar or the standard E-09?
I run the Dakar version and it has a very stiff framework. Great for the harder terrain but not very ...