Thumpstar 90

[yfz450inMI]

So is anyone running these? Look very similar to the Apex machines just not as wide.

http://www.wolfpackracing.com/images/thumpstar_pro.jpg


Like the Polaris Predator 90 but better! Dual a-arms for better handling, Australian design, the coolest billet aluminum wheels we've ever seen, same motor as the Predator but this one is Liquid cooled, Hi-Performance (Chrome) combustion chamber exhaust, Racing intake and 24mm carb, Hydraulic rear brakes, nerf bars, a full inventory of replacement parts on hand!

Special Features
Double A-Arms
Race Tuned 90cc 2-stroke
Alloy Wheels
Alloy Nerf Bars
MX Handlebars
24mm Carb
Upgraded Suspension
Liquid Cooled
Racing Exhaust

Spec Link (http://www.omicronmotors.com/atv_pro.html)

[Valder]

Nice looking quad and liquid cooled as well. If we didn't have a DC90 now I'd be looking at that one.

[sadinkins]

you can buy these on ebay for around 1400 and that seems like a buy but you will need to widen them because they are narrow,my son also races a dessert cat 90 and i only wish it had dual a-arms.

[yfz450inMI]

There's a Super 90 and a Pro 90. The Super 90's sell for $1400 or so on ebay.

The Pro 90's have billet aluminum wheels, nerf bars with heel guards, race tuned engine and pipe, 24mm carb, and MX style handlebars.

Besides being narrower than the Apex model, anything else I should be aware of?

[wrhracing]

I have had a couple Thumpstars in too make them run correctly.
When you uncrate it may be so rich that the motor will not rev far enough to engage the clutch.
Here is what you'll need to do. Right off the bat.
Put 4.5 gram rollers in it. ( It has only 3 roolers in it now for speed limitations).
Change carbureation to 40 or 42 on the pilot. Up the main from the 85 or 90 to at least a 92 ,95, 97.5. possibly a 100.
Replace air filter with a Uni. And try to get one with a off-set flange.
Change and bleed the green water out, and replace with anti freeze mix.
Run performance based fuel.
The engine will be quite soft in comparison to the Apex. It feels like a horse and a half at the seat of the pants. I tried the race size wheel assy's on it. It helped slightly on bottom.and livened the upper mid up.
You'll still missing a upgrade in the engine , engine performance,
Wheels tires, axles , disc brakes, ac racing package. etc.

Still a good base package. Just narrow and heavier and detuned. (Or seems like it).
Gotta Go.

[Valder]

[i]my son also races a dessert cat 90 and i only wish it had dual a-arms. [/B]

I have a guy locally that is working on a set of Dual A Arms for the DC 90. If they work out I'll be getting them and posting it here.


Darrin

[wrhracing]

The Thumpstar pro's would make a good narrow Cross Country bike. It turns tighter then the wider units available.