DRZ400S Europe restrictions

[RaulM]

Hi everyone,

Over an year ago I bought a DRZ400S, 2007, with 6000km on the clock, in absolutely new condition. The only thing that bugs me isnthat I’m 100% sure it’s restricted.

I rode a buddies, and his is a beast comparing to mine. Mine won’t go over 105km/h, and it’s very lazy getting there. It feels more like a 250CC.

Could you guys advise how to de-restrict it? It’s a European spec DRZ.

 

Thanks!

[bumtarder]

This is the procedure to de-restrict an old EU spec DRZ;

https://www.thumpertalk.com/forums/topic/518525-euau-pair-valve-solenoid-removal/?tab=comments#comment-4893446

 

 

[deweym21]

The most basic thing you can do is do the 3x3 modification and use the JD jet kit or mirror it's settings with the proper components. This is a major improvement even with the stock exhaust. Some improvement can be made for wide open throttle performance with an aftermarket exhaust and the appropriate jetting settings but with the stock exhaust and the aftermarket needle pilot and main jet settings you will effectively wake that bike up. If you have money to spend and can get a new fcr 39 jetted for your setup would be even better. Try doing one thing at a time. Be aware if you change something after that baseline jetting such as an exhaust you will need to rejet and adjust the needle

[DrzDick]

This thread might be helpful, it seems that if you have a restrictor it will be the carb top cover.

 

 

[Syntax_Erol]

If carb selonoid seal gone bad its always leaking air to top of the carb, thus not opening throttle %100 ever, removing a perfectly working selonoid doesnt change much but you should take a look there 

Also on A2 restricted bikes carb top cover have some extrusions that prevent slide to go up fully

Edited February 10, 2022 by Syntax_Erol

[RaulM]

Thanks everyone for your replies! 

I'll first start with the carb cover, take is out and compare it to my pal's. If they are the same (which I doubt), I'll start looking for an air intake restrictor, if that's also not the case, then I'll go the pair valve removal.

My gut feeling is that the carb cap is the issue here.