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Discussion Starter #1,101
Got the drive pulley situation fixed. There was one hole that had damaged threads and one bolt snapped of a quarter inch down in the hub. Cleaned it up got a new spcenter spacer, the old one was ground up. So now the pulley fits good no movement without the bolts in it. Put red lock-tight on all and got new longer grade 8 bolts that went all the way to the bottom of threads with a shoulder through the pulley and down into the hub a half inch. Torqued them good and tight. We'll see if this holds up.
 

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Discussion Starter #1,102 (Edited)
The "Death Wish" project roars on. Spent the last few days shaking out any weak spots. The nitrous has been off line and tanks are empty. The last dyno run gave us concerns over the transmission after seeing the numbers it made. So this video is just the motor no with no NOS. Had to break in the transmission after its super duty overhaul and upgrades. and strength test the the driveline after we snapped some rear drive pulley bolts. Everything is holding up fine now. Running good. Gonna throw it up on the table and change out all the oils now that it's been broken in. Gonna fill the NOS bottles and get it back on the dyno for one last time tune with the NOS then it'll have full power back again. Second run started wander off the edge of the road, its difficult to steer while the front wheel is hovering off the ground...

 

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Discussion Starter #1,105
OK that that damn tail weave is still there... Grrrr.... I think I'm on to what is causing it though. I have narrowed it down to the swingarm itself. I think the swingarm is flexing laterally. A tad of history for those who haven't been following, I never had this problem before the 124" was installed. I believe the high torque is what is initiating it. I have a paucho chrome swingarm witch is basically the same as the stock arm on my 89FXR. Today I was racing someone and as I approached 90ish under full power the rear of the bike started oscillating to a tail weave. If I do back off it amplifies. Every other area has been addressed. Everything has been upgraded including first losing the rear spoked wheel suspecting spoke flex so it now has a mag wheel. The swingarm bushings have been replaced with solid bronze tracula bushings, trans case is not egged out and shaft has no play there. Stainless pivot shaft so much more rigid than stock, new rubber isolators with steel stiffy incerts so should be little to no movement there. All new heavy duty stabilizer links in front, top, and even added a third from the frame to the oil pan at rear of transmission so nothing is moving latteraly there either. Urethane alloy art front motor mount. New wheel bearings in rear mag wheel. New alxe in rear as well. Ohlins shocks. There is absolutely nothing else to do to make this thing track better and yet it's there..... What I suspect is the swingarm itself is causing the issue. Was considering doing the tube frame under the swingarm but that is for chain only as the belt has to go through it. Making a removable section would only cause a loss of rigidity. I'm contemplating making a one piece plate to weld to the bottom of the swing arm. I doubt anything in the front of the swingarm box section is flexing I assume it right where the rectangular tubes exit the box section and go to the axle. That would be the weakest point. I'm convinced this has to be the cause. I'm pulling it apart tomorrow Che king the axle and pivot shaft for straightness and will probably be cutting some plate and welding it in to shore up that swingarm point. I gotta get this fixed the NOS can get me to the red zone so fast it's scary. Tail weaves suck. I'll take a front end shake any day over a tail weave... It's seems under full power it way worse than just normal acceleration. Thought I had this cured but it isn't..... I'll keep you posted
 

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Discussion Starter #1,106
Went to a bike show last night with my son and his bike, the rigid chopper we built together two years ago. He hasn't ridden it in over a year. He had a crash last year. It wasn't bad just shook him him up a bit. He's been a little gun shy since. He finally decided to get back in the saddle again. Was pretty cool he took first place and I took second place. Father and son win. Caught a quick video of the purge system on my bike. I finally got around to fixing the nitrous system. Snapped a fitting a few months ago had to re configure it a little
 

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OK that that damn tail weave is still there... Grrrr.... I think I'm on to what is causing it though. I have narrowed it down to the swingarm itself. I think the swingarm is flexing laterally. A tad of history for those who haven't been following, I never had this problem before the 124" was installed. I believe the high torque is what is initiating it. I have a paucho chrome swingarm witch is basically the same as the stock arm on my 89FXR. Today I was racing someone and as I approached 90ish under full power the rear of the bike started oscillating to a tail weave. If I do back off it amplifies. Every other area has been addressed. Everything has been upgraded including first losing the rear spoked wheel suspecting spoke flex so it now has a mag wheel. The swingarm bushings have been replaced with solid bronze tracula bushings, trans case is not egged out and shaft has no play there. Stainless pivot shaft so much more rigid than stock, new rubber isolators with steel stiffy incerts so should be little to no movement there. All new heavy duty stabilizer links in front, top, and even added a third from the frame to the oil pan at rear of transmission so nothing is moving latteraly there either. Urethane alloy art front motor mount. New wheel bearings in rear mag wheel. New alxe in rear as well. Ohlins shocks. There is absolutely nothing else to do to make this thing track better and yet it's there..... What I suspect is the swingarm itself is causing the issue. Was considering doing the tube frame under the swingarm but that is for chain only as the belt has to go through it. Making a removable section would only cause a loss of rigidity. I'm contemplating making a one piece plate to weld to the bottom of the swing arm. I doubt anything in the front of the swingarm box section is flexing I assume it right where the rectangular tubes exit the box section and go to the axle. That would be the weakest point. I'm convinced this has to be the cause. I'm pulling it apart tomorrow Che king the axle and pivot shaft for straightness and will probably be cutting some plate and welding it in to shore up that swingarm point. I gotta get this fixed the NOS can get me to the red zone so fast it's scary. Tail weaves suck. I'll take a front end shake any day over a tail weave... It's seems under full power it way worse than just normal acceleration. Thought I had this cured but it isn't..... I'll keep you posted

The 124" engine is not the source of the weave that you are experiencing. Between my bikes and the guys i ride with, I have visibility on at least 23 FXR with 124: engines. These bikes have suspensions that range from worn out original factory stuff to the best fo the best components with every little aftermarket do dad available. None of them weave. I think the mistake that many make is in alignment and the various adjustments for the chassis. The thing with the fluorescent light tubes is only slightly better than guessing. Have you considered taking the naked bike to a motorcycle chassis shop like GMD Atlanta?

GMD Atlanta Computrack

There are other shops that do this. I only post this as an example. I have been into FXRs since long before they were cool. and have built many of them from bare frames. I have yet to find an oem FXR frame that was not out of spec. This includes a cherry '00 FXR4 with 12k miles on it. Yea, it had some twist in the neck. Get that bike into a professional chassis shop. One that deals with race bikes. They will get right down to the root source without any band aids.
 
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Discussion Starter #1,108
Yah I'm in NY so no where near those guys. A ways back somebody mentioned it could be an aerodynamics issue as in the fender, chin spoiler, or dash cowling possibly as well. Unfortunately I can't really run it with out the dash on..I can keep fiddling with the alignment though. Maybe bust out the lazers when it's up on the table next time
 

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Yah I'm in NY so no where near those guys. A ways back somebody mentioned it could be an aerodynamics issue as in the fender, chin spoiler, or dash cowling possibly as well. Unfortunately I can't really run it with out the dash on..I can keep fiddling with the alignment though. Maybe bust out the lazers when it's up on the table next time
There is a lot more to it than simply aligning the front and rear wheels and leveling the drivetrain to the chassis. Seriously. The idea of building a custom bike on a frame that is around 30 years old without having it checked is not really the best course of action.
 

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Discussion Starter #1,110
The frame was checked over and tacked down to a heavy steel deck table and everything checked out OK before I started building. One thing I did change was the fork length to +3" and put on 0° pro-1 trees. It did end up bringing the wheel back a touch so I suspect the trees it had were probably +3°. This was when we did the Cafe build first, I wanted handling over high speed stability and raised it for cornering with the belt drive. Went up to 14.5" shocks from 12" Other than that everything is stock geometry. It's very possible the weave could be caused by rake angle. I just feel that due to happening when under hard throttle it would have been in the rear. Flexing swingarm.. Could be wrong.
 

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Of Note... If the trees brought the wheel Back, it is De-Raked.. which is OK to maybe Good... if the trees are in fact Raked Out... +Rake.. they can be extremely Dangerous...as the Rake can be Dangerously Reduced... Only Good for Sidecars, and Tricycles..
 

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Discussion Starter #1,112 (Edited)

Closing the post down for a while..or at least till the next build..I was the guy on the 1989 Harley. When the spinning,flipping and sliding ended I was left with a snapped in half femur some broken ribs, road rash from being blown down the road and some other injuries. I did however survive...long recovery ahead. Was infront of an MC and made a u-turn to park in front. While mid turn i was hit on front fork area by a pickup doing 70mph., driver was wasted drunk, and then he fled the scene. Bunch of guys infront of MC took right off after him. Got him three blocks away. He apparently " fell down" a few times before police got there.
The bike sustained some heavy damage. Don't know if its fixable as it and the truck are in impounded pending criminal investigation. I will update at later date after recovery. Thanks to all who followed
 

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Oh No! Sorry to hear it, sounds like you got banged up, but of course it could've been worse. Praying for a full recovery. I hope your buddies "straightened out'' the drunk driver before the cops got there.
 
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Hate to hear that. Hope you have a speedy and full recovery.

Sent from my SM-A102U using Tapatalk
 
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That sucks! Best wishes for a complete and quick recovery.
 
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