Topic: 520 Chain conversion?

[Coldsmoke]

Greetings,
I'm looking to put 520 chain and sprockets on a 73' 350F as these bikes need all the help they can get. Anyone know what model bike used the same components but in a 520 size?
Thanks

[kyre]

I just ordered 520 sprockets from http://www.sprocketspecialists.com/ for my 400F.  The front was around $20 and rear about $50 or $60. The rear is aluminum so get the hard anodized black option as it'll last longer and is only $15 more. They are very nice and informative, just let them know your bike and how many teeth you want on each.

[Coldsmoke]

Oh!  That sounds great. I've dealt with them in the past and look forward to doing so again. Thanks for the tip man !
D

[Coldsmoke]

Ok, I just got my 520 sprockets for my 350f (thanks kyre and others) .  I really dont like the set up with the front sprocket....its of course about 2.5mm narrower than A 530 but there is no shim or spacer to stop it from floating that much, and they give you a clip to hold if on insted of the stock bolted retainer.

Should I be remotely troubled  by any of this?

[kyre]

Hey Coldsmoke, I was worried about that too. Using the clip is fine, what I was worried about was the extra space. I just measured the OD of the spline and bought some shims from http://www.mcmaster.com/#standard-shims/=lzm6tx  with the same ID.

[Harsh]

Are you thinking about putting the shim on the inside or outside of the front sprocket?  I would think that if you put it on the inside that you would need shims on the rear sprocket as well so that they are both spaced equally which would provide proper alignment of the chain.

[Coldsmoke]

Thanks for the shim source!  What I did for now was used the  stock retainer as a shim which took up most of the play..I also located it on the outside thus holding the sprocket inward. My logic being that the narrower 520 rear sprocket will be sitting "farther in" due to how its mounted so I should match this with the front...This holds water right?

[alacrity]

actually - think of it this way.  A 520 is 1/4" wide, a 530 is 3/8" wide.  So the 520 1/8" narrower than a 530.  That's 1/16" on EACH SIDE of the sprocket.  Ergo, the chain travels "only" 1/16" closer to the hub in the rear. You'd need to center the countershaft sprocket to align to where the rear sprocket settles when the rear end is all bolted up and torqued in place.  So all other things being equal,  it will by definition then require a little spacer behind the sprocket and one between the sprocket and the retainer. But things may in fact NOT be equal.  You need to measure the precise thickness of the OEM sprockets at the mounting points (countershaft center and along the rear sprocket boltholes) and then compare those numbers to the thickness/width you get from the replacement sprockets. This will tell you precisely how much "spacing" you need to keep the sprockets snug and aligned.

IMHO. YMMV. Best of luck, etc etc....

[UFgatorEE]

actually - think of it this way.  A 520 is 1/4" wide, a 530 is 3/8" wide.  So the 520 1/8" narrower than a 530.  That's 1/16" on EACH SIDE of the sprocket.  Ergo, the chain travels "only" 1/16" closer to the hub in the rear. You'd need to center the countershaft sprocket to align to where the rear sprocket settles when the rear end is all bolted up and torqued in place.  So all other things being equal,  it will by definition then require a little spacer behind the sprocket and one between the sprocket and the retainer. But things may in fact NOT be equal.  You need to measure the precise thickness of the OEM sprockets at the mounting points (countershaft center and along the rear sprocket boltholes) and then compare those numbers to the thickness/width you get from the replacement sprockets. This will tell you precisely how much "spacing" you need to keep the sprockets snug and aligned.

IMHO. YMMV. Best of luck, etc etc....

You don't have to do that.  Both sprockets are mounted using the right face of the sprocket.  Picture this, on the stock sprockets, if the middle of each sprocket is in line with each other, and the sprockets are the same width, then the right face of each sprocket must also align.  Both sprockets mount using the right face.  So if you buy narrower sprockets, add spacers to the same side of each sprocket to make up the difference (i.e. mate a spacer to both left faces, or both right faces).  A picture would probably make more sense, so try drawing it.  Just don't add a spacer to left face of the front sprocket and the right face of the rear, that would throw the sprockets out of line.

I would add the spacers to the left face (outside of bike).  This mounts the sprockets as close to the output shaft bearings as possible, which will put less stress on the output shaft and bearings.

[bollingball]

Well this will drive you all nuts I don't do any shims on the front just get the rear where I want it and let the front float as long as the rear axle is true with the front shaft then the front sprocket will center its self. My front sprocket has a 2mm lip that goes to the inside to keep the chain from ever making contact with the seal. I do not have the same bike but I see no reason why the front should not float other than the one I mentioned.
Ken

[kmb69]

On both the 350 Four and the 400 Four, when sitting on the bike, the front sprocket is aligned to the left by the "Plate, Drive Sprocket Fixing". The rear sprocket is more or less aligned to the left as well by a washer and circlip. You could use a single 1/8" shim on the inside of the rear sprocket to align with the new front. Or, as someone already suggested, use a 1/8" shim on the left side of both to move both sprockets in. Or, use a 1/16" shim on the left of the front and a 1/16" shim on each side of the rear to maintain alignment. Probably not advisable to let the rear sprocket float side to side on the boss of the rear hub.

[kghost]

Or just use the stock 530 and quit mucking about lol

[CoachDoc]

Or just use the stock 530 and quit mucking about lol

+1. The only reason I would go through the rigermarole this conversion requires is if I wanted to run an o-ring chain on my 550. Otherwise why bother.

[kghost]

Or just use the stock 530 and quit mucking about lol

+1. The only reason I would go through the rigermarole this conversion requires is if I wanted to run an o-ring chain on my 550. Otherwise why bother.

Well I said it in jest.......

However, I was thinking the same thing.

Racing? I have a hard time thinking its gonna make a whole lot of difference.

I did modify my 400 wiring to the battery so I could use the same battery in both the 350 and 400....... But that's just being pedantic