Do you not have the larger fuel pump and fuel regulator?
I was just wondering why the race fuel? I’m running the same AFR’s pump gas 91 on the same tune.
WinterWolf
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TAPP is cool cruising or Wide open. Pro 4 is warm wide open it seems(that’s on rail bed averaging 70-95mph with bursts to wide open, and this for 20-30 miles).
XS 825 seems to be holding up fine so far.
WinterWolf
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No Allens or washers on through bolts. Sorry for the delayed response..N. Maine just got buried yesterday/last night with 18-20” Blizzard, and internet was down.
ISLANDRACING
Extreme
I had more belt dust with the XS825 in 50 miles than there was with the 8DN in 275 "put it to the test, all-out corner-to corner" miles. Rpm was about 200 higher with the 8DN, which i will adjust with the roller bolt and washers ( same as adjusting tip weight ) vs using the clicker.
KnappAttack
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That’s because you guys are over pinching the xs belt. It does not need the added pinch in the secondary the 8dn does.
They both require a different clutch setup.
They both require a different clutch setup.
WinterWolf
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IMO if you’re using the TAPP Primary with the XS...you’re gonna need some pinch in the secondary, cuz the TAPP will pull the belt right through the secondary so fast, you won’t have the performance if you don’t increase your spring pressure some in the secondary, cuz you’ll be doing more belt slipping through the secondary. This is what I’ve found.
Tcat100
Expert
Agree completely, you need a lot of pressure in the secondary cause the TAPP is a squeeze monster. That's why I went with the 32 helix. That's how I finally got the secondary temps under control. But I do have a bunch of dust, the least of the potential problems IMO.
KnappAttack
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Then I'd have to say your setup is way wrong, cause the XS825 just flat out does not slip like the Yamaha belts do. If you are pinching the secondary that strong you are loosing efficiency and just building heat and making belt dust.
Put a normal setup in the secondary and tune the front clutch accordingly. When you pinch that hard in the secondary it keeps a hold on the belt and will not let it go out of the secondary. The only reason I ran heavy springs in the secondary was to keep a hold on the slipping Yamaha belts. You don't want to hold the secondary back because the front clutch is too heavy and aggressive. Efficiency comes from the secondary, let it shift with the lighter normal springs and only grip the belt as hard as it has to without slippage.
I know of one TAPP primary machine on a 320HP pump gas setup, running a Viper secondary and has a normal, old school helix in it, using a Dalton Red secondary spring in it. He took a bunch of push and weight away on the TAPP to make it happen. Its like as light and non aggressive as it goes. The Dalton red is a weak spring!
You guys are all overdoing it up front and the balance is way off if you have it pushing that hard that you are controlling RPM in the secondary with heavy springs on the 825. If I'm not mistaken you on stock muffler tunes and not even running the big tunes!
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WinterWolf
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Im not controlling RPM’s with my secondary.
TAPP is a whole different animal. TOMMCAT set mine up with the Dalton springs. He knows his stuff. But the secondary needed to keep up with the extreme pull of the TAPP primary. TAPP Is pulling proper R’s..secondary needed to keep up. So I adjusted with a lil more wrap. And it Made a big difference for me. You can see where the belt was slipping in the secondary a bit after engagement.
ClutchMaster
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Your running an 8dn belt setup, it will be hot and inefficient with the XS belt. The least amount of belt squeeze you can use will make it the most efficient and fast period.
If you over squeeze a belt it wedges into the sheaves and causes heat and poor efficiency. Knapp and any other experienced racer will tell you this same thing.
Take the shared knowledge on this site to improve your setup. I have learned a lot from these guys testing the XS belt!
Giving a shout out too Knapp, Fleecer and Jon the crazy Frenchman.
PS
I’ve been running the XS for 4 years, I had no idea you could go this light on the setup, thanks guys!
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WVTurboLTX
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Why are you mixing fuel on MS17? That's all I run and have never seen a knock light.
****EDIT***** Never mind. Got to your answer above. I've got the button on the bars and have been clicking up to MS20 in the twisty stuff with no knock light as well. I would never hold it on that tune without mixing though.
STAIN
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I have a TAPP primary also and find it to be very aggressive. I have @2000 miles on it along with a Pro-4 secondary. The way I received the clutch it was set up very heavy and the only way to make it work was to run monster secondary springs. I have gotten away from that and taken a bunch of primary weight out and changed the secondary spring. That being said I have working to get my secondary spring pressure down. I am struggling to find the PERFECT balance. Every time I seem to get close I run out of adjustment on the primary.
Primary is empty with +1 rollers and I am just shy of running 8900. In desperation I added 1 hole of twist to the secondary. I then started to slip the primary slightly on long 50-70 mph runs ( rail bed), one line in the middle of the primary face. 43-32 helix with Cat green spring. I am also using the TAPP blue primary spring---the softest. XS 825 belt with NO issues.
I am contemplating going to stock size rollers to get my rpm up then have the ability to run a softer yet secondary spring and have some adjustment in the front. Or put the secondary spring back and let it run.
The other thing I have yet to get my head around is the effect of roller weight vs. arm weight---is it the same? they are very close in proximity. I ask because I also have an issue where is it over-flashes off the bottom by @400 rpm before it settles back and slowly begins to climb again. If it where a regular flyweight clutch I would have some ideas but have yet to grasp where to place some of the weight in the arm yet or if it matters.
Testing has been hard this year with low snow and real poor ice conditions.
I will say that on the 270 SMT it is strong on the bottom and is a BRUTE in the midrange, very strong pull. I am just trying to make it as close to perfect/efficient as possible. I would also like to get a set up where I am not at the end of the adjustment, just seems like when I get close I am maxed out on adjustability.
Maybe I just think about too much!!!
Primary is empty with +1 rollers and I am just shy of running 8900. In desperation I added 1 hole of twist to the secondary. I then started to slip the primary slightly on long 50-70 mph runs ( rail bed), one line in the middle of the primary face. 43-32 helix with Cat green spring. I am also using the TAPP blue primary spring---the softest. XS 825 belt with NO issues.
I am contemplating going to stock size rollers to get my rpm up then have the ability to run a softer yet secondary spring and have some adjustment in the front. Or put the secondary spring back and let it run.
The other thing I have yet to get my head around is the effect of roller weight vs. arm weight---is it the same? they are very close in proximity. I ask because I also have an issue where is it over-flashes off the bottom by @400 rpm before it settles back and slowly begins to climb again. If it where a regular flyweight clutch I would have some ideas but have yet to grasp where to place some of the weight in the arm yet or if it matters.
Testing has been hard this year with low snow and real poor ice conditions.
I will say that on the 270 SMT it is strong on the bottom and is a BRUTE in the midrange, very strong pull. I am just trying to make it as close to perfect/efficient as possible. I would also like to get a set up where I am not at the end of the adjustment, just seems like when I get close I am maxed out on adjustability.
Maybe I just think about too much!!!