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'07 fork spring swap

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Hi All,

I've been using my '07 WR450F for MX duties but the super soft forks are making my life very hard. I have to land every bump and jump on the back wheel, as if I'm riding some 60's scrambler. Landing front wheel first or even large braking bumps cause the forks to bottom out with a loud whack! I've tried fiddling with the oil height but even a max recommended it's still the same. 

The stock springs fitted are 4.5N. Yamaha max recommended is 4.6N. Surely a 2% wont be enough? I'm thinking of trying 4.8N (6.6% stiffer) 

I'm not hitting 130ft tables so i dont need it super stiff. I'm about 70kg. What are you guys using? And did you fit more/less preload spacers??

Thanks in advance

Pancho 

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WR OE springs are usualy under-rated...WR's are notorious for it

My 08 which was also supposed to have 0.46 in actually measured 0.41

Put some real 0.46's or what ever is the recomened for your weight in and you'll amazed at the difference (unless you're about 8st)

As said above, the base valve is also a joke...the race tech conversion works well and stops the harshness over  ripples and tree roots and bottoming out from jump landings

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Thanks for the info Guys, unfortunately I'm on a little Island in the English Channel so not super easy to order from Racetech but I'll give them a call and discuss.

Love the bike but the forks are that dire I almost convinced myself to buy an '18 when/if they become available.

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1 hour ago, Pancho_Jsy said:

Thanks for the info Guys, unfortunately I'm on a little Island in the English Channel so not super easy to order from Racetech but I'll give them a call and discuss.

Love the bike but the forks are that dire I almost convinced myself to buy an '18 when/if they become available.

Do something those forks dive so bad through the travel due to the bad base valves, you could get hurt.  Fork springs will not help it. 

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PDQ in uk are the uk importers for racetech  so very easy to get the racetech stuff

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8 hours ago, stevethe said:

Do something those forks dive so bad through the travel due to the bad base valves, you could get hurt.  Fork springs will not help it. 

I beg to differ..the springs will help but will not solve it on their own as wont just the base valves on thier own

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7 minutes ago, GuyGraham said:

I beg to differ..the springs will help but will not solve it on their own as wont just the base valves on thier own

I guess that depends on what you weigh. I have three wr450's and every one dived right through the travel to the harsh mid stroke. The Racetech valves fixed everyone of them without new fork springs. Even the Supermoto but was later upgraded to Ohlins. 

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I ran .48 fork springs and 5.8 rear in my 11 WR. I did not do much track jumping tho but I do weigh 225 with gear and back pack. It rarely ever bottoms out but a big jump may do that. I do race hare scramble with big G outs and big rocks.

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Thanks for the advice Gents, I've emailed PDQ to get prices and availability. I'll fit the valves and have a test ride. If its still too soft I'll up rate the springs too. Gotta be a lot cheaper than a new bike! 

PS. Anyone wanna buy a 2011 Husqvarna TC250??

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you get a code with the kit, to plug into the racetech website that allows you enter your weight, age, ring style etc and it gives you suggested settings for the shim stacks

within the kit itself is a table showing you in incremental steps the shim stacks required to go harder or softer that there suggestions

Once you have the kit you will understand better

They have taken out a lot of the guess work and 'mystery'

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