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GasGas newbie questions

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Some quick questions from a first time GasGas owner (2020 GP 300).

  1. What 2T oil do you run and how much in 5 litres?
  2. What gearbox oil do you use. The book recommends Motorex but it seems quite expensive and hard to come by.
  3. What's the best plug to use in the UK? I think it comes with a BPR5ES as standard. Has anyone used one of the iridium plugs?
  4. I've been told that any 300 GP that comes through JSM (this one did originally) gets a low compression head insert and re-jetted. Can anyone back this up? I've asked Shirtys but they haven't got back to me yet. Anything else that you know they do to the bikes from standard.
  5. How does the low compression head on a GP compare to the standard Racing model?



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Answers to Questions 1 & 3

I use Putoline Trials pro 70ml in 5litres petrol, that's 70:1.

Standard sparkplug BPR5ES I doubt you'll notice any difference except for the prices.

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I hope this helps:

-Putoline mx9, 65ml to 5 litres of oil.

-Putoline light gear oil (75w) works well for me. 

-Double check the plug on the GP as I seem to remember they have a different plug to the standard bike due to the s3 cylinder head but could be wrong. (I think they run a short reach plug) Standard plug is fine.

-Yes shirty preps them with a low comp head which makes them less fierce and very smooth (still very pokey with the low comp head). You’ll know what insert it has as they are colour coded(you can see insert colour where the plug screws in) (gold for low comp, silver for standard, red for high compression). I believe the jetting may just be a pilot jet change. To be honest the standard jetting is very good, some go to a 3 slide once run in but I’ve never felt mine needed richening. 

-The racing model has a standard compression insert from the factory, the GP comes with a high compression. There’s not a huge difference from low comp to standard but I’d say the low comp is easier to ride and suited to most people. You can always play around with inserts for relatively little money to get it how you want it. 


Edited by hugh_b
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65ml to 5lts mx9, putoline nano trans, standard plug. Shirty sets them up perfectly 45 pilot low cpmp head, leave as is, power is perfect. Ride it as it comes.you wont find a better set up.

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