2010 450 spring set up


13 replies to this topic
  • fraser

Posted January 12, 2010 - 02:03 AM

#1

Hi guys, a little help on the rear spring please. Just trying to get my new bike set up for my weight (10.5 - 11 stone) A knowledgeable friend who does a lot of supsension work says I'll definately need a softer sprinfg on the back, and probably in the forks as well.

Just read a recent test in a UK mag that thought the forks came a little soft, so I'm hoping they'll be ok for me. Now the rear, I read on here that 106mm race sag was the way to go, what should the static be though? I have a new spring that came off my 06 250F, as I swapped that out for a softer one. Its the one that came standard which is the trick lightweight titanium one.
I'm hoping this will be just about perfect in terms of spring rate, but will it fit the shock? Guess I won't know until I try, just wondered if anyone thinks for any reason this is a bad idea?

Cheers

  • NE14MX

Posted January 12, 2010 - 05:48 AM

#2

I don't know how much a stone is. The .47 fork springs are softer than I normally run at 185lbs. and what I believe is vet B speed. The tests I've read say they work well though for that weight/speed. For you the Ti spring may work well because the stocker is 5.7 and they say you should run one rate lighter when you run a Ti spring so the 5.5 stocker should act like a 5.6. After setting your sag, measure the static (unladen) sag. If it's more that 40mm you need a softer spring. If it's less than 30mm you need a stiffer spring.

  • Dr.Crankenstien

Posted January 12, 2010 - 06:14 AM

#3

measure that ti-spring it needs to be 260mm in length.

  • saccityfire

Posted January 12, 2010 - 08:47 AM

#4

A stone is 14 lbs. per Wikipedia. That means that Fraser is between 147 and 154 lbs. I would say that he needs softer springs as the stock bike is targeted at a 175 lb rider. Fraser is 21 to 28 lbs lighter than the "target" weight. Of course if you're riding supercross, it may be just about right.

On a separate note however it takes large stones for a smaller guy to ride such a big bike and my hats are off to ya Fraser.

  • Bambislayer

Posted January 12, 2010 - 12:05 PM

#5

A stone is 14 lbs. per Wikipedia. That means that Fraser is between 147 and 154 lbs. I would say that he needs softer springs as the stock bike is targeted at a 175 lb rider. Fraser is 21 to 28 lbs lighter than the "target" weight. Of course if you're riding supercross, it may be just about right.

On a separate note however it takes large stones for a smaller guy to ride such a big bike and my hats are off to ya Fraser.


Especially if his "stones" are 14 lbs.:banghead:

  • grayracer513

Posted January 12, 2010 - 12:20 PM

#6

Hi guys, a little help on the rear spring please. Just trying to get my new bike set up for my weight (10.5 - 11 stone) A knowledgeable friend who does a lot of supsension work says I'll definately need a softer sprinfg on the back, and probably in the forks as well.

Just read a recent test in a UK mag that thought the forks came a little soft, so I'm hoping they'll be ok for me. Now the rear, I read on here that 106mm race sag was the way to go, what should the static be though? I have a new spring that came off my 06 250F, as I swapped that out for a softer one. Its the one that came standard which is the trick lightweight titanium one.
I'm hoping this will be just about perfect in terms of spring rate, but will it fit the shock? Guess I won't know until I try, just wondered if anyone thinks for any reason this is a bad idea?

Cheers

At 165 lbs. an '09 YZ450, which comes with .47 kg/mm springs in the front, and a 5.5 kg/mm at the rear, would call for .44's and a 5.2. Your '06 YZ250F came with a 5.1 kg/mm spring, which is close, and might work. The 2010 comes with a 5.7 rear spring, however, so it may be that you'll need something closer to a 5.4. You could try it and see. You can use your sag settings to determine if the rate is correct or not:

Set the Sag: http://www.tootechra...ension_tips.htm

Check the Spring Rate: http://www.tootechra...pension Tip.htm

  • jeffboyd47m

Posted January 12, 2010 - 05:13 PM

#7

Springs from anything earlier then 2010 will not interchange on the new bike. You have to order 2010 specific.
JB

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  • sherco67

Posted January 12, 2010 - 05:43 PM

#8

crf's and kxf's springs are a little bit wider than yamaha's earlier ones, I put a 5.3 Kawasaki spring on mine after powder-coating red, and set up is fine at 150 pounds with gear on, free-sag is 36-38 mm. front is still pretty balanced and will leave it alone. and if you have a tuner use map 7, works great for vet b rider. good luck and grease linkage while your in there.

  • grayracer513

Posted January 12, 2010 - 05:55 PM

#9

... if you have a tuner use map 7, works great for vet b rider. good luck and grease linkage while your in there.

The tuners do not come loaded with maps by default. Please post this "Map 7" of yours in the EFI Maps DB so others can use it. Use the template in post #1.

  • fraser

Posted January 13, 2010 - 08:38 AM

#10

Thanks for the tips guys. I'm going to try that Ti spring as its just sitting there. I'll let you know how it goes. Jeffboyd, why do you think it won't work?

  • sherco67

Posted January 13, 2010 - 02:54 PM

#11

inner diameter from yamaha spring is too small for shock body, I loaned tuner out and waiting for friend to send the fuel/timing numbers I have on it, will post as soon as I get them, thanks

  • jeffboyd47m

Posted January 13, 2010 - 05:35 PM

#12

Jeffboyd, why do you think it won't work?


I don't think, I know! I have a 2009 that I wanted to swap springs with my 2010. I called Enzo to make sure they would work and was told no. The fork springs are a different length and the shock spring is a different diameter. The stock 5.7 spring works perfect for me with my 205lb weight set at 105mm of sag. I put in .48 fork springs with 10cc less oil and have been able to adjust the clickers till I'm happy with the stock setup.
JB

  • fraser

Posted January 14, 2010 - 01:42 AM

#13

:banghead: D'oh! Seemed like a great idea, thanks for the info, looks like I'll need a new spring then

  • fraser

Posted January 19, 2010 - 12:37 PM

#14

Its true I'm afraid. Not that I didn't believe you guys, but just wanted to double check as I had all the bits there. The 250F spring is around 3mm too small internal diameter to fit the collars at either end. :banghead: Cheers





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