Chain

[DSengineer]

Now that I think about it I may have got my front steel 520 sprocket from Ron Woods. I ran a 15T but at your weight you may like a 14T better.

Everything on the DS is over engineered. Part of the reason it weighs so damn much... If your concerned about it, and beat on your DS pretty hard riding across rocks and such by all means stick with the 530 setup.

[Wreckr]

I ride about 50% in the dunes and 50% on trails and river bottoms and such. The price of the 530 setup is what's most tempting. Obviously the 520 is more sought after, so of course is going to be more expensive.

Maybe I'll just CNC Machine my own sprockets... >=)

[justme23005]

Originally Posted by DSengineer

Your comparing apples to oranges. Your 1000cc street bike motor is probably turning 3x the rear wheel HP of a stock Rotax motor.

All chains will have some amount of stretch when they break-in. There are plenty of good quality 530 chains out there that are just as stong as a 530 when used on a DS. Every sport quad on the market (including the Raptor 700) uses a 520. In my opinion the 530 is complete overkill on the DS. It makes sense to go to a 520 setup if your going to be replacing chain and sprockets anyways. The saving in "rotating" mass, not dead mass is pretty significant and will free up a couple of HP and let the motor rev quicker. I have run a 520 DID X-ring, Rocky Mountain front steel, and PBI rear aluminum on my HPR cam/piston stock bore and had no significant stretch after break-in or signs of significant sprocket wear after 2.5yr of use.

I never said that it was on my 1000cc project quad.. It was on my 04, which only has a high compression piston, & aftermarket cams.. And the project quad is actually closer to 4 times the horsepower of a stock 650.

[DSengineer]

Your definatly the first I have ever heard of stripping a steel 530 front sprocket on a DS. Definatly not the norm. I would say you either had a faulty sprocket or poorly adjusted chain for that to happen.

BTW a stock DS makes around 42-44HP at the rear wheels. A few boltons and your making close to 50HP at the rear wheels. I don't think your FZ1 is making anywhere near 200 RWHP. THe FZ1 bikes are turning 130-140HP at the rear wheels and you are going to be making less than that due to additional drivtrain loss.

[justme23005]

Originally Posted by DSengineer

Your definatly the first I have ever heard of stripping a steel 530 front sprocket on a DS. Definatly not the norm. I would say you either had a faulty sprocket or poorly adjusted chain for that to happen.

BTW a stock DS makes around 42-44HP at the rear wheels. A few boltons and your making close to 50HP at the rear wheels. I don't think your FZ1 is making anywhere near 200 RWHP. THe FZ1 bikes are turning 130-140HP at the rear wheels and you are going to be making less than that due to additional drivtrain loss.

This sprocket is only the second one I've seen broken like this, in 20+ years of working in, & owning motorcycle repair shops.

BTW. Real STOCK DS650 RWHP is 38-39. Here is one of many dyno charts on it. BOMBARDIER Advertised H.P. is rarely the same as a real dyno run. especially when looking for RWHP, instead of the engines bulk H.P. My FZ1 engine STOCK, pushed 140 H.P & 120 RWHP.

Yamaha FZ1 - Wikipedia, the free encyclopedia
5.6 US gallons (21 L) (2001–2005). Related, Yamaha FZ6 ... The FZ1 was carbureted and produced around 140 hp (100 kW) (118–120 hp at the wheel). ...
en.wikipedia.org/wiki/Yamaha_FZ1

Then, We got rid of the airbox, installed pods, & a custom Mudge Racing jet kit, Timing advancer, & Akropovic pipe, and a few other goodies :-) We ended up with 146 RWHP. Almost 4 times what it was stock.. :-D