Grubee GT5 w/high compression head issue

Discussion in '2-Stroke Engines' started by Matts22366, Jul 2, 2015.

  1. Matts22366

    Matts22366 New Member

    What's up guys, I just bought a GT5 pro kit and it came with a high compression head, and I was reading "Jaguars" posts on some mods that must be done to prevent det. What are those mods? Also what are some mods that should be done first CDI, exhaust, carb????

    thank u much,

  2. MotorBicycleRacing

    MotorBicycleRacing Well-Known Member

    Whatever kit you bought from gasbike was not made by Grubee.

    Grubee has not shipped any kits to the USA for a long time and
    they do not have a business relationship with gasbike.
  3. KCvale

    KCvale Motorized Bicycle Vendor

    Absolutely correct.
    Gasbike hasn't had any real Skyhawk anything for a couple of years, they just continue to use the name, just like they still call their EPA illegal 66cc engines 80's.

    Don't get me wrong here...
    I don't want to see gasbike go away as they import hundreds of things I often need, but the new actually good quality stuff from the YaunDong (Skyhawk) factory are headed to the US now and beside a couple of vendors like I am working towards being a supplier of good cool stuff I like myself.

    I know, way off topic, but what the heck, relevant 1st hand facts ya know?
    I generally wouldn't even dip my toe into in a lake of uncertainty but I am weighing my options for authorized parts supply with actual real support as I kinda do that now for free, but everyone has to eat ;-}
  4. Matts22366

    Matts22366 New Member

    Ok well my question was an I going to have a problem with the high performace head will it damage my motor, should I buy a new CDI ???
  5. jaguar

    jaguar Well-Known Member

    yes, with high compression you need the Jaguar CDI because its retarded timing matches the higher compression.
    get a gauge and make sure the cranking psi is not more than 135psi.
  6. Matts22366

    Matts22366 New Member

    I understand ase what about those product, does it have switches for different retard/advance settings? Also are u familiar with the kit I got, it's the GT5 kit from, and it comes with a high comp head So my question remains what CDI should I buy, your jag that's $75 or do I have another choice as far as a performace CDI goes? Also what other MODS should I do first to obtain optimum performace for example, different carb, jetting, exhaust...... What should be first?

    Attached Files:

  7. butre

    butre Well-Known Member

    keep in mind, jaguar makes the jaguar CDI and is trying to sell his product. his CDI is certainly a good product that will improve engine life, but running a different CDI such as the HD Lightning or Rocket CDI or even the stock unit isn't going to kill your engine. there are plenty of racers using the stock CDI with compression figures exceeding 170 PSI. of course, they're killing bearings and rings much faster than most people, and the cylinder plating only needs to last a few miles.
  8. KCvale

    KCvale Motorized Bicycle Vendor

    Just a note about the gasbike GT5 engines, they are not real GT5's.

    Grube Skyhawk GT5 engines are made in the Yuan Dong engine factory and gasbike can't buy them.
    Like their fake GT2 gastank frames, they are just using the good name.