Derestricting 97 DT125r

[sloanparkes]

Hi there, I am new to this site and I have a question I can not find anywhere
I'm wanting to derestrict my DT, its got a full dep pipe on.
Now I've read a load of stuff, some say it's the reed switch amongst other things and usually not even for 97 dt.
If anyone could help me out, it's stuck at 60mph an no more than 7000 revs. I know it can do alot more.
If it is the reed switch, anyone know what colour it on my DT?
Also I've seen loads of links to that dt125r.net.... but every time I go to use it, it doesn't show me anything besides links that aren't anything to do with derestricting a 97 dtr
Any help would be greatly appreciated, many thanks in advance

[declan]

@sloanparkes I can never really find anything out other than an older CDI mines a 1990 but the engine must be newer as it redlines really early similar to yours

[NINJA]

@sloanparkes our good friend @scrimsmustang wrote the book on how to de-restict;

https://www.slideshare.net/kerryprinceuk/derestricting-the-yamaha-dt125-r-1988-through-to-2007-scrimsmustangs-classic-yamaha-restorations

[declan]

@ninja I’ve read that a few times ans couldn’t find anything to help me out since I already have an exhaust and such

[sloanparkes]

@ninja said in Derestricting 97 DT125r:

@sloanparkes our good friend @scrimsmustang wrote the book on how to de-restict;

https://www.slideshare.net/kerryprinceuk/derestricting-the-yamaha-dt125-r-1988-through-to-2007-scrimsmustangs-classic-yamaha-restorations

That says it only goes up to 96 model:/ mine being a 97....

What should I do just sell it and let someone else struggle with it? It's really getting at me that I've got all that power but it just loses it all at or around 7000 rpm

[Calum]

@sloanparkes Sounds like the powervalve isn't set up to me.

[declan]

@calum I’m finding something interesting out bud I don’t know if you remember but when I first started posting about my dt I would complain that it only revs to 8.5 then hit limiter but since I’ve been adjusting the power valve so it lines up perfectly with the circle hole I’m only getting around 7.5k then redline which is making it difficult to ride off road I’m a little confused because I can physically hear the limiter sound but I’m certain it used to rev higher

[NINJA]

@sloanparkes Scroll down bud, page 2 covers 97-99 models.

[NINJA]

Also I have to concur with @Calum If the PV is incorrectly set-up that will narrow the exhaust outlet and thus reduce power. Always worth spending a bit of time getting that adjusted perfectly before splashing cash elsewhere.

[Calum]

@declan I've never bothered setting it up against the hole.

Personally I take the exhaust off and make sure it's flush with the port.

[declan]

@calum but have you ever set it up in the port then looked at the hole and the hole not be lined up? I’m gonna have to do that I think because it’s gotta be off

[Calum]

@declan parallax bud. When you understand that you will underdtand my issue.

[declan]

@calum I’ll have to look that up,it’s getting worse bud I’m at 6k redline now just been on a big enduro ride and I can see now that the pv is retarding

[declan]

@Calum ahh I get it yes it’s gonna have to come off It’s getting annoying

[sloanparkes]

@calum said in Derestricting 97 DT125r:

@sloanparkes Sounds like the powervalve isn't set up to me.

Ya well I've moved it back the other way... but it doesn't reg above 65000 in 5th and still sat at 60mph ish I'm so sure it's restricted...

And ya @NINJA it was right at the bottom and my toolbar on my phone was covering it saying 97 to 99 cheers dude