I was looking at gasgas.com parts break downs on some random models and it seems that GG has retained the same Pv spring for 200-250-300 for many years. Thats not saying that they didn't change the spring deminsions or rate and retained the part number. The only different part number on my random search is the 125's. I'm not sure whether it would be stronger or weaker or if they would fit in the other bigger bikes. That would be opening a can of worms as far as expirementing. The stock spring could be rated and measured and possibly there are springs available somewhere with different rates. The stock spring apparently has a leverage ratio that is low tolerant because of the super thin shims that are installed to affect rate. On the other hand there is an extreme difference in the KTM springs supplied with the newer bikes. The red spring is the weakest and can be compressed easily by hand. The green spring is very stiff and the yellow in between. The difference in the power delivery is very noticable. The green spring makes the power very mild and in my opinion is only good for extreem tight slimmy conditions.The leverage ratio on the PV spring I believe is way different from GG to KTM. That said , I think a little bit will go a long way on the GG. JMHO