520 Conversion?

[billster]

This kit looks interesting.

Has anybody gone this route, chain and sprocket sizes?  Worth it?  Wondering about top end....I STILL find myself trying to shift into that phantom 6th gear too often.

Billster  

[2005B12S]

I would not bother. The only reason to go with 520 is for weight, on a 500lb steel framed bike it is a waste of time. You could lose the centerstand and save as much weight with out spending any $.

The 520 kits are popular on the GSXR bikes as weight is hard to reduce on a bike that already weighs in at 400 lbs.

I am using a 520 kit on my '83 GS750ED rebuild as I need the smaller chain to help with rear wheel alignment as I am using a 2001 Katana 750 4.5in rim with a 160 radial on the rear. Premium 520 chains are just as strong as a 530, so you do not give up any strength. Photo below.

Ride On, Ed.
2005 GSF1200SZ
1983 GS750ED

http://groups.msn.com/SuzukiGSGarage/gs750edbacktolife.msnw?action=ShowPhoto&PhotoID=3335

[bandit0914]

I was curious about the conversion too. Not for the weight reduction but for the torque and acceleration. But like Billster I seem to try for the 6th here and there. Will this kit lower top end and compromise power? Has anyone used vortex products? How is the quality?

[Red01]

This kit looks interesting.
Has anybody gone this route, chain and sprocket sizes?
Worth it? Wondering about top end....I STILL find myself trying to shift into that phantom 6th gear too often.

They're recommending to drop one up front AND go up two in the rear? Seems to me that would cut back top speed  - and make wheelies VERY easy... Just one of those changes in gearing will up the wheelie quotient, let alone both together. You'd be looking for 6th even more frequently than today with this gearing!

You'd certainly notice a lot quicker acceleration, but it would be more a function of the gearing change that the loss of mass. To get an accurate feel for how much the smaller chain and lighter sprockets made, you'd have to back-to-back compare them in stock gearing.

Premium 520 chains are just as strong as a 530, so you do not give up any strength.

How do you figure?

DID 530ZVM (premium street chain) has a tensile strength of 10,400 lbs and a Wear Resisance Index (WRI) of 3,700 (the higher the number, the longer it lasts), 100 links weigh 5.04 lbs.
DID 520ZVM has a tensile strength of 8,545 lbs. and a WRI of 3,400, 100 links weigh 3.67 lbs.


DID 530ERV (premium race chain) has a tensile strength of 9,340 lbs. and a WRI of 3,630, 100 links weight 4.37 lbs.
DID 520ERV has a tensile strength of 8250 lbs. and a WRI of 3,450, 100 links weigh 3.53 lbs..

The chain offered in the ebay ad (the GXW is the RK premium line):

RK 530GXW has a tensile strength of 10,000 lbs. and a WRI of 1,000, 100 links weigh 4.63 lbs.
RK 520GXW has a tensile strength of 8,400 lbs., 100 links weigh 3.75 lbs. (couldn't find the WRI # for the 520).

I was curious about the conversion too. Not for the weight reduction but for the torque and acceleration. But like Billster I seem to try for the 6th here and there. Will this kit lower top end and compromise power? Has anyone used vortex products? How is the quality?

Vortex is great quality, one of the tops in the sprocket biz.
The kit in the link will likely reduce top speed, but acceleration will increase. Fuel mileage will take a hit, too, but you may not notice it as much with the odo being off unless you measured your mileage with a GPS instead.

Stock Sprocket sizes are 15 tooth front 45 tooth rear which has a final drive ratio of  3.00 Our optimum ratio is 14 tooth front 47 tooth rear which has a final drive ratio of 3.36

Extensive testing on the street, eddy current dyno and on the race track have proven that this is the optimum ratio for your bike, however you may choose any combination of front and rear sprockets for your application.

I'd be interested to see the numbers from their "extensive testing" . . . if they really did any.

I'm curious how different it is from 14/45 (3.21) or 15/48 (3.20), which is what many people gearing downward go to.

[2005B12S]

Premium 520 chains are just as strong as a 530, so you do not give up any strength.

How do you figure?

DID 530ZVM (premium street chain) has a tensile strength of 10,400 lbs and a Wear Resisance Index (WRI) of 3,700 (the higher the number, the longer it lasts), 100 links weigh 5.04 lbs.
DID 520ZVM has a tensile strength of 8,545 lbs. and a WRI of 3,400, 100 links weigh 3.67 lbs.


DID 530ERV (premium race chain) has a tensile strength of 9,340 lbs. and a WRI of 3,630, 100 links weight 4.37 lbs.
DID 520ERV has a tensile strength of 8250 lbs. and a WRI of 3,450, 100 links weigh 3.53 lbs..

The chain offered in the ebay ad (the GXW is the RK premium line):

RK 530GXW has a tensile strength of 10,000 lbs. and a WRI of 1,000, 100 links weigh 4.63 lbs.
RK 520GXW has a tensile strength of 8,400 lbs., 100 links weigh 3.75 lbs. (couldn't find the WRI # for the 520).

I am using a RK GB520GXW on my 750 project. It is rated at 8800lbs tensile strength.

An average DID or EK stock replacement 530 chain is rated app. 9300lbs- this is about the quality of your stock B12 chain.

Therefore replacing a stock 530 with a Premium 520 chain does not really sacrafice any strength- 500 lb reduction in strength is less than 10%.

As far as wear, obviously it will wear faster, but I don't look at that when going for all out performance. Kinda like tires- give me the sticky ones.

I have seen a ton of 520 conversions on GSXR 750/1000's and R1's. All of these bikes produce more rear wheel hp than a slightly moded B12.

We probably agree it is not a sensable mod for a B12, you could spend the amount of the purchase price of a GSXR1000 and still not get this beast under 400lbs.

Ride On, Ed.
2005 GSF1200SZ
1983 GS750ED

[Red01]

Yes, we do agree a 520 conversion isn't sensible for the average B12 rider. It's primarily a racer's mod, and they don't care about the chain lasting for thousands of miles. Probably not even a season, since many racers carry different chains and sprockets for different tracks. Any GSXR rider that opts for a 520 conversion and expects long life will be in for an awakening.

It's odd that your chain is 400 lbs stronger than what they list on the RK site, but maybe there's been a change between when the web info was posted and when your chain was made. According to their chart, all the GB prefix means is the link plates are gold colored and there's no indication this changes strength either way.

I thought you were comparing Premium 520's to Premium 530's. Yes, the OEM B12 chain is a lower grade O-ring and is probably only marginally stronger than a Premium 520. OTOH, if you were to opt for a Premium 530, you should expect a much longer life than what you'd get from a stocker.

The thing that really caught my attention between the RK & DID chains though was the wear index! The DID has a 3.4-3.7 times higher wear index.

[billster]

LORDY!  This has certainly become an interesting thread....learned a lot.  I'm stickin' with the stock setup for the road.

Thanks, guys.

Billster

[2005B12S]

Bill, you started it all BTW, very nice Boxer, I work with a guy who has restored 2 of them.

If riding a modern 600 or 750, I would definetly do the conversion. The only reason I decided on it for my dinosaur 750 was to help with rear wheel alignment. I am going from a 3.5in rim/ 140 tire  to a 4.5in rim/ 160 tire. I am already using an offset countershaft sprocket and figured the narrower 520 chain would help. Motor is still apart so the jury's still out on this one.

I picked the RK only because it was the strongest 520 chain listed. The 750 is going to be quite a ride when done and should give my B12 a run for the money.

I previously used the Tsubaki Sigma 530 O-ring on my 750, it is an excellent chain- I averaged 15,000 miles of very hard riding before replacing. This was on a very pumped up 750.

See You Guys, Ed.
2005 GSF1200SZ
1983 GS750ED