Mileage and Speed

[Gadzooks Mike]

Well, yeah. What I'm saying though, is that I'll bet (a cold beverage of your choice) that they're all off the shelf parts and not specific to Suzuki, just to a 525 chain and assembly. I doubt Suzuki stamps out sprockets, but instead gets them from Spacely, and it's probably the same sprocket used on a bunch of stuff, not just Suzuki. JT isn't going to make them anymore, but somebody is.

[jonathan180iq]

If you look on the JT website, they have a cross reference chart and you can match up dimensions from sprockets for other bikes. Then, even if Jt doesn't have it, you can search for that sprocket made by another manufacturer.

[Jaime]

I've been searching for similar sprockets at the JT website for a while, and the only one a bit similar is the JTF 432, but there's no 16T version :mad:


I can't believe they're discontinuing this model, can't GZ250 owners even replace their 15T sprocket for the same one?

Anyway, if you really need a longer ratio, you can buy the JTR 819.39 rear sprocket and make the bolt holes bigger. You'll get slightly shorter gears; that means, at 6500 rpm in 5th now you do 69 mph with a 16T, you'll do 67 mph using a 15T front / 39T rear, while stock speed is 64.6 mph at same rpm.



I've made an Excel table to calculate speed variations because of sprocket changes, but it's in km/h. :roll:

[Jaime]

Well, I've converted the xls chart for you. Now it's in English and in mph.
It can be used for any bike, knowing the gear ratios and the tire that mounts. You can only modify yellow cells, so there's no way to ruin the file. :tongue:

http://rapidshare.com/files/53542278/RATIOS.xls.html

I hope it serves you!

[Water Warrior 2]

To the best of my knowledge Sunstar used to make sprockets for Suzuki, probably still do if that helps.
Years ago( this was a fun exercise )a friend of mine wanted a one tooth smaller front sprocket for a 1988 DT 200 Yamahussy. Dealers would not even look beyond the factory parts book and said you are SOL. A kindly parts guy at a Honda dealer went through his entire stock comparing sprockets and Bingo, we had one. Was for a 125 CR motocrosser. After getting a couple longer bolts and extra washers for the install the bike was climbing hills far better and had some real get up an go.

[Gadzooks Mike]

Thanks, Jaime!!

Water Warrior, that's my point exactly. I've got to have a talk with George Jetson. He works for Spacely Sprockets, and I'm pretty sure he can find one that fits. In the meantime, I'll see about Sunstar!

[Regular Guy]

Hey fellas,

I bought my 16T sprocket from Rebel gears, they make a lot of their own gears but got this one for me from one of theri suppliers. I'm not sure who, but we discussed it a bit and Rebel guy told me it was the same except had a boss shoulder, to try it and see if it works. It did-perfect fit. can remember exactly, maybe about $20 + dollars.

Just thought you would like to know!

ps: can anyone tell me how to insert a link with this editor?

Is it like this [www.rebelgears.com][/url]

[trykemike]

Glad to hear from you Mike.

Re: the different models SUZUKI installed the 250 engine in several different models from the early 80 until present

they are :

GN250 , TU250 , GZ250 , Marauder 250 .

I have read power ratings ranging from 15.2 lbs torque @5500 rpm and 22 hp @ 8500 rpm to
14.8 lbs torque @ 7000 rpm 20.6 hp @8000 rpm.

gear ratios are the same only wheel sizes vary but so also do the tire profiles.

dry weight ranges from 285 to 305 lbs

there are some jetting differences 115 main vs 120 main jet

I have a tach so I know my bike will rev to 8000 rpm in 4 th and 7750 in 5th because I have done this many times.

It may even hit 8000rpm in 5th but I never have enough space to try it ( usually 1/2 mile ) clear max.

I have checked the spark plug it was a light tan color .

[Badbob]

I like this one. Note the kick starter.

[Badbob]

I like this one even better.