Actually I haven't ridden since I got back from my trip. Still have 612 miles or so.. I will leave on a trip the 26th-31st up north somewhere.
I wasn't going to be testing clutch kits.. Must be someone else you are thinking about? I'm very impressed with the clutching on my F7 so I'll be leaving it stock.. Super response and backshift, and great gas mileage too! :wub: How can I improve on that? B)
You no, I was thinking the stock kit was good to, But want to get a highter engagement, If I buy some weights I bit heaver and grind a flat spot in them I think I can get want I want from my stock clutch, same RPM shift and all that whth just a higher Engagement, Does that sound right??
if you just want a higher engagement, put in the next stronger spring. Spring controls engagement and weights control shiftout. Course, they overlap and it's not quite that simple, but that's the general idea.
With a higher engagement, you will slip the belt more at low speeds.. I can't believe how low this thing tachs at 20-35mph.
I no it does tack in low, I am use to my ZR at 5,300 Rpms and took off like a rocket, clutch kit was in it when I got it., But I read that if I Just grind a flat in my weights but dont change the weight I can keep what I got with a higher engagement, So I was thinking of getting a heaver weight and grinding a flat spot in the low area of the weught so it is harder for the weight to over come the spring that is in it. This should work right?
The only problem with a notch or flat spot is that its harder on the rollers. The only time you really need a notch or flat is when you can't accomplish to get your desired engagment RPM with spring. There are many choices of after market springs to help maintain your desired shift speed and engagment.
Personally, I am leaving my clutch stock. My buds out in NE Oregon run drags when they are not powder riding.
They are going to be running Heavy Hitters with a Pink/Pink spring I believe is what they said. I don't know much about it, maybe Dan can shed some light on the set-up.
I was told if I change the spring, I would have to change everything, But If I keep every thing the same, and do the flat spot trick, I should get what I want without changing anything, Maybe I will Just get A clutch kit.
SabercattF7, I would highly advise against grinding weights if you do not have a grinding block and a gram scale. The easiest fix is to buy a different spring to increase engagement. Stock Yellow/White 122/285, AC Orange/White 143/290, D&D Yellow 160/290. The first number is the engagement rate the second is the shiftout rate in lbs. As you can see the AC Orange/White will only raise the engagement slightly and the D&D Yellow will have a significant effect on engagement. Since the shiftout rates are within 1% you will not see a change in top speed RPM.
The AC Orange/White will raise your engagement approximately 250-300 RPM the D&D Yellow will raise your engagement approximately 600-650 RPM. Remember there is usually a 5-10% tolerance on rates of springs. A given spring may be stiffer or softer than those rates I quoted, thus changing engagement RPM. Clutch kits are designed to do different things. One kit may accelerate very hard but lose top speed, the next kit may not accelerate as well but cause a gain in top speed. The manufacterers generally have good all around clutching but can be improved upon depending on your individual preference. It is really hard to develop a kit that will show big gains in both acceleration and top speed. When purchasing a clutch kit be sure to specify your specific application. Rob is right, the F7 clutching is very good for all around performance. It will be hard to improve on in all areas. Accelerates, backshifts, and pulls very well on top end. What are you trying to achieve? Some manufacturers spend countless hours developing good all around clutch performance. It takes an experienced tuner to make improvements.
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