Hello everyone,
Im a rookie to this, and I have no idea of where to buy parts for this ATV. I bought my daughter a 2005 Eton Viper 90 and it is ok but I want it faster. Any advice on how or what I can do to it? Where can I purchase parts for it. What is the easiest thing I can do to it to make it faster.
Thanks in asvance for your responses.

 

You'll need the stage1 kit to start.
Usually a bigger carb, reed cage and reed, and a pipe.
WRHracing.com
Hetrickracing.com
Tell em I sent ya.

 

Thanks LT80,
I was told if i change the coil and CDI box that it would make a big diff. is that true?
The Viper 90 does not have that quick take off, what do you advice? It idles great and once its going it picks up pretty good.
Lucio

 

I believe the 2005s had an adjustable CDi box..The higher the number you turn the dial to the higher it will rev...If it doesn't have the dial simply snip the green wire coming out of the back of the cdi and it will rev unlimited.....Over the past five years or so I have done some tweaking on my sons viper 90..I got rid of the stock air filter and installed a UNI..You will need to rejet the carb for this to work...I also lightened the rollers in the variator for better acceleration from a stop..Also added some boyeseen reeds for good measure..This made the bike accelerate much better but didn't really add any top speed.......In fact the lighter rollers slowed down the top end a little..I changed the front sprocket to one with 3 more teeth to get the top end back..It also had the added bonus of moving the chain up and away from the swingarm...

Finally this year I added a pipe..It dramatically changed the characteristics of the engine making it a very high rpm screamer but absolutely killing the bottom end power..The key to making it work was lots of clutch tuning and some lighter shoes on the rear clutch to help up the engagement rpms....Adding a 24mm Kiehin carb didn't really seem to help much much to my surprise....Finally I added a new 53mm piston and cylinder to up the CCs to 92 from the stock 82....The porting is much bigger in the new cylinder and really added to the torque of the engine..With the new pipe Speed jumped from about 27mph to over 40!

 

luciog,
Depends on what you are trying to accomplish and what you want to do with it. Racing is one thing, trail machines have a totally different requirement (mud and water, etc)

Get the engine tuned in first, then start with fine tuning the clutching with a stiffer rear torque spring and lighter front variator weights to target the RPM's at the peak HP of the stock motor. This alone is an improvement, the OE exhaust on the later Vipers were pretty good compared to others.
Alot of guys spend the $$$ for the cylinders, pipes, carbs, etc only to not go any faster because they don't have the knowledge to tune what they already had...
In addition these asian mini quad engines are scooter derivatives so there are way too many different components that will fit (cylinders, intakes, ignitions, etc). However, so many of these together in a combo won't provide a good results because of unoptimal compression or port timing which will hurt performance.
Reality is the chances of buying 12 different things on Ebay, bolting them on, and actually getting it to gain performance is slim to none. You have to know what your looking for and what does what with what else... what needs what to offer an actual gain.

Example, a few years ago my daughters STOCK '05 DS90 was beating other modded 90 quads at alot of 300ft drag races. At that time we had never dug into the internal engine or carb, only fine tuned the stock clutch parts and gearing...