How To Remove Swingarm & Swap Differential

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bikedave99

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Alright, so now I have the wheel, shocks and stock mufflers off. It is not necessary for all of this to be off in order to pull the swingarm but it is was done as I was working on other items. Next I will be pulling the swingarm so that I can replace the bearings and swap on a Venture differential I scored on ebay. Put jackstands under the swingarm to support it as it is no longer resting on the muffler.

So, this is where I am starting:
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You don't have completely remove the rear brake arm but I am going to as I will be messing around with the swingarm and would rather have one less part flopping around:
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Next I pulled of the side covers:
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I unbolted the left side passenger footrest bracket. This is not necessary for the job but I really like to have things opened up, especially if it is the first time I have pulled it apart:
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Then you can either unplug the regulator/rectifier or unscrew it from the bracket. In fact, it would probably be a good idea to pull it off the bracket and clean the screws/bolts/holes as this is how it grounds to frame I believe:
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Unbolt and remove the right side passenger footrest bracket. Once again, this is not necessary just opens the area up:
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Pop the chrome caps covering the swingarm bolts:
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Bend back the tabs locking the nut inplace on the left side:
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I only had one large metric socket bigger than 19mm and it just so happened to be exactly the size of the nut, which I believe is 27mm. Go ahead and loosen up the nut:
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Loosen and remove the nut on the right side:
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Then get our your allen wrenches and back out that stud:
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Here it is:
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And here is the fully removed 27mm bolt from the other side:
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Now the next step is to gently pull the whole sucker out the back. It is a little cumbersome. I'm sure you could start by removing the pumpkin so that it is less heavy, but I didn't think of that. Here it is after it is out:
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And here is the swingarm sitting on the ground with the boot still on:
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I had lost the spring retaining bungy thing that was supposed to keep the rubber boot tight, and I thought that it was getting a little loose and floppy. Apparently I was right and it was a little stretched out. Thankfully I had already ordered one from Pinwall Salvage. Check out the difference!
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Ok, I'm now going to drain the differential oil out of the pumpkin. I will also make sure it is drained on my new Venture pumpkin:
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Next, I am going to have remove the shock stud from the Vmax differential and put it on the Venture differential. I believe the Venture diff I have is from a 1987 bike so it is already drilled and tapped for the stud and does not have a cover on it. Just a simple transplant but it could give you some trouble as it is just a stud which is threaded on both side with no good way to grab it to twist it out. This gave me heartburn for a little bit, but eventually I just got out the visegrips and latched on as hard as I could and it twisted free. I then took the visegrip induced burs off the stud with a file and twisted it into the Venture diff:
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I then pulled the four bolts holding the pumpkin to the swingarm:
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The shaft will pull out with the pumpkin as it is just a splined joint which slides into the u-joint at the back of the tranny. The shaft will also just pull straight out of the pumpkin, it may take a bit of tugging but it is not mechanically held in. Ask Mark (maleko89) if there are any risks inherent in pulling this shaft out... Anyway, here are the two pumpkins and shafts next to each other. As you can see, the Venture shaft is roughly a quarter inch longer than the Vmax shaft so be sure if you are buying a new pumpkin that you get the shaft with it. It may not be entirely necessary but it is a little bit more engagement:
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Next, I am going to pull the bearing races out of both sides of the swingarm. So I go borrow a pilot bearing puller and slide hammer from O'Reillys and use that to pull out the race. With the right tools, this is very easy:
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Alright, get both bearings and races out, here are my old and new bearings:
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I also borrowed a bearing driver tool from O'Reillys which was nice for tapping in the new races. Yes the driver is on backwards as they didn't have the perfect size for these bearings and were prone to getting stuck.:
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Then take a small punch and tap around the race to make sure it is fully sealed:
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Repeat with the other side. Be sure to put a light coating of grease on the races before you tap them in.
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Grease up the bearings and put them in the races and press in the rubber seals on top. There is a metal collar that sits in the seal and I found it helped to put the collar and seal in at the same time so that the seal seated properly. I then bolted on the venture pumpkin. I believe other have waited to install the pumpkin until the swingarm is installed but I wasn't sure if I would be able to find the u-joint with the shaft if I did this so I went ahead and installed the pumpkin:
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That is the last of my pictures as it took me all of my arms and legs to then install the swingarm. Like I said before, you apparently don't have to install the pumpkin until the swingarm is in place but I didn't do it that way. Be sure to follow the torque specs on the swingarm bolts as you are installing and frequently check to make sure the collar in the bearing seals isn't cockeyed. Once you get it bolted up semi-tight, cycle the swingarm to make sure it is smooth and wiggle it to make sure it is tight. When you reinstall the rear wheel and axle bolt, be sure and loosen the four bolts on the pumpkin to let it align squarely with the axle. Then retighten them. Don't forget to fill it up with differential oil and go!
 
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I need to note that the mufflers and passenger pegs/supports do not need to come off remove either the arm or diff.

Sean
 
I need to note that the mufflers and passenger pegs/supports do not need to come off remove either the arm or diff.

Sean

Thanks Sean, I'll edit that in. It has been a little bit since I did it so I couldn't remember how necessary that was. Either way, for a couple of bolts I like to just clean it out so I can better see what I am doing. Appreciate the input as always!
 
Excellent write up for the How to section. :clapping: Thank you!! :cheers:
 
Thank you for this write up bikedave99 all your photo's with the step by step of this 'How to Guild' I was able to tear into my project of swapping out my oem swing arm for a braced one. Being I had never messed with a shaft drive before, I had no problems getting all my old parts off, I did have to place a call into SEAN to get the axle into the U joint. I was trying to mount swing arm with pumpkin on it and get it all lined up, it was not working. Sean told me to pull the drive shaft / axle out of the pumpkin and mount the swing arm then slide the shaft / axle into the U joint then mount the pumpkin on the swing arm. But never the less thank you for your write up.
 
Thank you for this write up bikedave99 all your photo's with the step by step of this 'How to Guild' I was able to tear into my project of swapping out my oem swing arm for a braced one. Being I had never messed with a shaft drive before, I had no problems getting all my old parts off, I did have to place a call into SEAN to get the axle into the U joint. I was trying to mount swing arm with pumpkin on it and get it all lined up, it was not working. Sean told me to pull the drive shaft / axle out of the pumpkin and mount the swing arm then slide the shaft / axle into the U joint then mount the pumpkin on the swing arm. But never the less thank you for your write up.

Glad it helped! Nothing like a few pictures to boost confidence. I will say that the last few times I have I have done this I have definitely NOT installed the pumpkin first. Once the swingarm is in place I look down the arm with a flash light and use a wooden dowel to get the U-joint centered up in the opening before stabbing the shaft down it. I will even leave the dowel in while trying to thread the shaft in to keep the U-joint propped up. Dunno, each time is a little different!
 
Just a little tip, to get the stud out of the pumpkin without damage, just lock 2 nuts together on the thread you can see, then turn the bottom one with spanner - simples!
 
Glad it helped! Nothing like a few pictures to boost confidence. I will say that the last few times I have I have done this I have definitely NOT installed the pumpkin first. Once the swingarm is in place I look down the arm with a flash light and use a wooden dowel to get the U-joint centered up in the opening before stabbing the shaft down it. I will even leave the dowel in while trying to thread the shaft in to keep the U-joint propped up. Dunno, each time is a little different!



I found that having U joint turned so the loose side pivots strait up and down allows for 'picking up' the threads and getting the shaft stabbed in easier. Just let it right lightly up the tube till it stops. Some slight wiggling and then you can rotate the final gear and watch for the drive to rotate in response.
 
Forgive my ignorance fellas....but what is the purpose of switching from an OEM differential to a Venture differential? I have a lot to learn...lol :ummm::confused2:
 
Forgive my ignorance fellas....but what is the purpose of switching from an OEM differential to a Venture differential? I have a lot to learn...lol :ummm::confused2:

About 10% higher ratio so revs drop and gas mileage better. I get about 44 mpg with mine installed. Wouldn't ever go back. Still has plenty of power and I don't race or do burnouts so don't need lower ratio.. :biglaugh:
 
I am in the process of doing this modification for the addition of my 17" Dymag magnesium wheels. This upgrade will lower my RPM's by about 500 and allow for better highway cruising not winding out the RPM's. Thanks for the visuals.....I dont have the venture shaft and dont think its necessary to swap them. Actually, I am just going to take my venture guts and put it in the spare vmax final drive casing so there's no difference.
 
With the smaller wheels you might wind up with close to stock ratios with the Venture differential. I used the V-Max shaft and have had no problems in the five or more years with the Venture unit.
 
Have come to this thread late, but am very interested in this modification. Understand about the length difference between the standard shaft and the one off the Venture, but what would the objection be to retaining the original shaft ?
Also, have all Ventures had the same drive ratio ?
 
Have come to this thread late, but am very interested in this modification. Understand about the length difference between the standard shaft and the one off the Venture, but what would the objection be to retaining the original shaft ?
Also, have all Ventures had the same drive ratio ?
None, you have to use the Vmax shaft. As far as I know, the Ventures are all the same ratio, Kyke or Sean would know for sure. Normal riding(steady throttle, 65-70 mph and a few burst) with a 17" rear wheel and Venture drive, I rode 123 miles before the light came n the other day in pooring rain. I've eeked out 150 miles on a tank of gas.
Steve
 
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Vmax final drive is 3.66, venture is 3.33. it's a 10% reduction in RPM over the whole range from stock. I got 42MPG with the venture final and about 36 with the stock one. I can't wait to see what I get with my new overdrive transmission.
 
Be sure to follow the torque specs on the swingarm bolts as you are installing and frequently check to make sure the collar in the bearing seals isn't cockeyed. Once you get it bolted up semi-tight, cycle the swingarm to make sure it is smooth and wiggle it to make sure it is tight.

I just replaced my swingarm with a stock powder-coated one. I did not have any problems getting the driveshaft back in but I am struggling with the swingarm pivot bolts. First: I put the left side bolt in and torqued it down, next I put in the right side allen bolt...this is when I had a problem. The bolt screwed all the way in easily and there isn't even enough threads to start the lock nut over it. If I back that allen bolt out some to get the lock nut on it then the swingarm is loose and moves side to side. What could have went wrong? Or a more better question is what did I do wrong?
 

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