Which weight works better for top speed? What's the pro and cons of one vs. the other. Just got a used 01 SRX with these 8Bu's in it.
YAMMIEGOD3:16
Active member
8DN20 WEIGHTS WERE USED STOCK IN THE 00-01-02 SRX WHEN THEY WERE NEW. 8BU ARE GREAT DRAG RACE WEIGHTS, THEY ARE HEAVIER AND HAVE A VERY AGGRESIVE SHIFT. I HAD GREAT LUCK USEING 8BU FOR TOP SPEED, BUT I WOULD SUGGEST YOU TRY BOTH AND COMPARE. THERE ARE ALOT OF NICE SET-UPS HERE WITH 8DN-20 THAT WORK GREAT IN THE SRX. 3:16 (yammie tony)
I dont have any 8dn20s laying around to compare. I know they worked great in my 02 srx. Just wondering if they are worth it for top speed runs.
8DN-20's are perfect fpr the trails when filled with 4.5 gram rivets. They provide alot more tip weight than the 8BU's for top end speed and help in back shifting.
The 8BU's have most of their mass at the heels to make the clutxh shift out ALOT more aggresively and have a flat spot at the heels to raise engagement. They do not have much mass at the tip to provide alot of top-end and do not provide alot of back shift. The 8BU-00 is a VERY good weight for short drags only.
http://www.totallyamaha.com/clutch_parts1B.htm
The 8BU's have most of their mass at the heels to make the clutxh shift out ALOT more aggresively and have a flat spot at the heels to raise engagement. They do not have much mass at the tip to provide alot of top-end and do not provide alot of back shift. The 8BU-00 is a VERY good weight for short drags only.
http://www.totallyamaha.com/clutch_parts1B.htm
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tomseal6 said:
Well said, and beat me too it. It all depends on what type of top speed you want? short drags, or lake/trail. if back shifting is needed, then 8DN-20's FTMFW!
Also,
The 8DN-20's have a fairly balanced shift curve in their profile which gives you all around performance on the trail
The 8DN-20's have a fairly balanced shift curve in their profile which gives you all around performance on the trail
Any thoughts on the 8dn-00 that come stock in the 98' SRX's?
mopar1rules
Active member
junk....that's my thought....lol. throw in some 8dn-20's....better replacement.
bluewho
Active member
I like them they weight more than 20s so if you need it they improve with 4.5 rivots as well.Junk is alittle harsh..they are very close on force values the 8 bu00 is way out there as the leader on the chart for qwick shift and holding top end forces on the chart.Equalizer said:
Looks like some 20's are needed! Also in this sled we have a 48/40 advant, green sec spring, and WWW primary.
mopar1rules
Active member
bluewho said:
i guess junk was a little harsh.....lol. the 20's have a better shift curve for the trails. the 00's are better for top end due to all the weight being distributed on the tip of the wieght, but the 20's are more balanced for a fine overall shift curve.
YAMMIEGOD3:16
Active member
TWO OTHER YAMAHA WEIGHTS ONE MIGHT CONSIDER IS A 8BU-10 AND A 89A-00. BOTH WERE USED IN VMAX 4,s. GREAT SPEED WEIGHT AND NOT THE AGGRESIVE DRAG RACE WEIGHT LIKE 8BU-00. 3:16 (yammie tony)
YAMMIEGOD3:16 said:
yeah, Thats the other weight I was going to mention. The 89A.
Thanks for the input!
seca
New member
8dn20-vs 8bu00 vs 89a-10's
i have used all three weights in my 99 srx 700 . 8bu's pulled very hard and had a great top end (pin it and don't let go)but had no back shift. i would not advise these weights for trail or off trail --deep stuff)89a-10's were a little better on the back shift -great mid pull -not so great on top end. 8dn-20's -- _loaded with 4.5 in both holes-white prim spring -green sec. spring. best of both worlds. nice bottom end pull, nice mid (a little racy)top end --around 180 kph. on a nice hard packed lake.
i have used all three weights in my 99 srx 700 . 8bu's pulled very hard and had a great top end (pin it and don't let go)but had no back shift. i would not advise these weights for trail or off trail --deep stuff)89a-10's were a little better on the back shift -great mid pull -not so great on top end. 8dn-20's -- _loaded with 4.5 in both holes-white prim spring -green sec. spring. best of both worlds. nice bottom end pull, nice mid (a little racy)top end --around 180 kph. on a nice hard packed lake.
I have seen any yammie oem weight win drag races. You get the rpm,s right & they will work. I saw a guy win a sanctioned drag race with 8dn-00,s in a 98 700 srx. He had em loaded with 7 grams in each hole with an engagement notch cut in with a stock secondary. rpm,s were perfect. The big trick is to get the rpm,s right with cool clutch temps. The motor does not know what weights the clutch is running & does not care. All the motor cares about is proper rpm,s & don,t slip the belt. There are a gazillion clutching combos out there that can help ya win. Rpm,s & proper shifting is the key. balance the primary & the secondary.
I use to think the 8DN-20's were junk. When I tried to trail ride the 8BU-00's, I found that they made my top-end suffer and would not pull very hard at the top of the power curve.
I would consider trying a set of 8DN-00's for 1/4 mile runs on the asphalt but not for trail riding.
I have heard of people welding metal or adding mass to the back side of the tip of the 8BU-00's to have some better top end. I believe Mrviper has a set like that.
I would consider trying a set of 8DN-00's for 1/4 mile runs on the asphalt but not for trail riding.
I have heard of people welding metal or adding mass to the back side of the tip of the 8BU-00's to have some better top end. I believe Mrviper has a set like that.
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bluewho
Active member
8dn 00 drilled out to take h/c tnuts and bolts with one washer on tip is what i use for trail rideing and ice drags.Seems like a all around great weight with the mods i have done with a 48/40 advantage or a bender helix.Compareing it to my sons 01 with dn20s and stock helix he cant touch me anywere but top end.
It's all in the SET UP like turk said for 1000ft speed runs i have a set up that will run 109mph with 8bu's.
