Topic: Finally got suspension done

[TexasTwister250]

Mock up with new suspension.

[Lamp]

Well... if you ever need a kidney, I think we could make a deal.

[Ricky_Racer]

Biotchin'!  Now, how about all the details?      RR

[singedebile]

that is gorgeous ,  down to the 'matching' fork and tank stripes. I cant wait to see the finishing touch's!

[ekpent]

Very Trick    -   Congrats

[TexasTwister250]

What did you want to know?  

The front end swap, I started by reading the post on here about a simular swap, can't remember the posters name right now but everyone read his long detailed project.  He had some problems and had to switch the main triple tree bar with the stock Honda bar/pin, I think this was because he started with a 600 front end.  I found a brand new 07 GSXR 1000 front end on ebay and the height was exactly the same as the honda.  With some conversion bearing it fit right up. I didn't have to but I machned down the bearings support lip on the top side about .300" to allow the bearing seal to sit below the top edge of the the frame.

[Ricky_Racer]

Thanks. Nice job. And what did you run into fitting the swingarm? Is it also from the same model of GSXR?  Thanks again.  RR

[TexasTwister250]

The rear started as a 2003 GSXR 600 Swingarm.  I picked it on a hope that the width would be close because it was only $30.  People dump these because they prefer the GSXR 750 swingarm that has the large brace hoop on it, it is probably stiffer.  But for the Honda I wanted a simple aluminum swingarem.  When I got it I fitted it up and the width was almost perfect but it was about 4 inches to long, made the bike look like a drag bike (see pic) so I had to shorten it.  This seemed simple but turn out to be a little complicated.

First I had to relocate the pivot, to do this I layed out where it need to be mounted measured if from every angle I could then drilled a hole on both sides which was tricky since both surfaces were on an angle, then cut the swingarm down the middle of the new pivot mounting holes.  I cut out the front pivot and ground away all of the weld on it to prep it then fitted it up to the new hole.  Here are some pics.  I will have to post the rest later I don't have them here with me.

[TexasTwister250]

Well... if you ever need a kidney, I think we could make a deal.

I will probably need a liver, there was a serious amount of beer required to think through all of the excellent and very enjoyable problems and technical issues that were encountered so far.   

[Ricky_Racer]

Outstanding! I wondered how you solved the issue of the swingarm length. We're looking forward to your seeing your progress on the project. Very well thought out.  RR

[domer]

any chain clearance issues? lookin bad ass...

[juice]

any chain clearance issues? lookin bad ass...

my thoughts exactly, how did you manage to align the 2 sprockets?

[TexasTwister250]

any chain clearance issues? lookin bad ass...

my thoughts exactly, how did you manage to align the 2 sprockets?

The chain alignment is off,  I calculated it at 3/4" and then confirmed it by measurement.   I am planning to solve this with several small solutions that will work together.  First is using a cycle exhange front offset sprocket that moves the chain 3/8" outboard, I am ordering it this week.  This is as far as you can go on the front with a 530 chain and not hit the frame, you could get more with a 520.  Next, the GSXR rear sprocket has an offset in it of about .150" that normally sits to the outside, by flipping it around I will pick up some more alignment, and third I made a shim that is about .120" thick that sits on the sprocket side of the axle to move the wheel over very slightly.  It is still close enought that the wheel looks centered on the frame and swingarm.  I could increase the shim thickness if necessary, but I think it will be close enought and I shouldn't need to.  Doesn't quite add up to 3/4, will have to eyeball it when the front sprocket is installed and see if it is enough.

[Retro Rocket]

Put the cycleX offset sprocket on the front and machine the rest from the rear sprocket carrier, thats what i did....

[hyde7278]

to shorten the swing arm could you have cut the amount out of the swing arm arms? Ive added to swingarms buy cutting the arm and welding in a piece so I would think you could do the same buy taking a piece out. I would think this would be easier then having to remount the pivot.

[TexasTwister250]

to shorten the swing arm could you have cut the amount out of the swing arm arms? Ive added to swingarms buy cutting the arm and welding in a piece so I would think you could do the same buy taking a piece out. I would think this would be easier then having to remount the pivot.

Couldn't get 4 inches out because of the angles, also this not a symmetrical swing-arm so it would have been difficult, then finally it would have made the tire hit the swing-arm brace in front of the tire.  Moving the pivot was more difficult but it was cleaner and more exact.

[Retro Rocket]

to shorten the swing arm could you have cut the amount out of the swing arm arms? Ive added to swingarms buy cutting the arm and welding in a piece so I would think you could do the same buy taking a piece out. I would think this would be easier then having to remount the pivot.

Couldn't get 4 inches out because of the angles, also this not a symmetrical swing-arm so it would have been difficult, then finally it would have made the tire hit the swing-arm brace in front of the tire.  Moving the pivot was more difficult but it was cleaner and more exact.

Your right, next one i do i think i will attempt it from the pivot end

[TexasTwister250]

So next I fitted up the cleaned up pivot to the cut swing-arm and leveled it with shims until it was perfectly level with the end of the swing-arm legs, and it was centered from top to bottom.  The swing-arm was to wide to have full suspension movement in the frame so it need to be narrowed on the 4 inches behind the pivot arm.  So, after centering the pivot, I removed it and made pre-cuts into the side of the arm but did not cut it all the way to keep the inside and outside surface of each side intact to maintain location until the pivot was tacked into the exact position.  Once it was tacked, then I removed a plate from each side to move the surface in about 1.25".  Next I went back to the welder to have the plates welded and the pivot welded into position.

[TexasTwister250]

Put the cycleX offset sprocket on the front and machine the rest from the rear sprocket carrier, thats what i did....

I was looking at that but when I measured the cush drive it was only 1.5" deep so I was not sure how much you could shave off and still be ok.  How much did you take off?

[wildcatmahone]

You might wanna get that Al swinger re heat treated back up to it's proper temper after all that welding.

[stueveone]

SLICK!

[Retro Rocket]

Put the cycleX offset sprocket on the front and machine the rest from the rear sprocket carrier, thats what i did....

I was looking at that but when I measured the cush drive it was only 1.5" deep so I was not sure how much you could shave off and still be ok.  How much did you take off?

I can't remember exactly, it was a while ago. I had it taken off the sprocket side of the carrier not the cush side. Take the sprocket off and machine the surface the sprocket bolts to. My rear wheel is off a GSXR750J, 4.5 inch, if i knew the original width of the carrier i could measure it ....

[Lamp]

This might be a little off topic, but I must know how you mounted your rear sets, and the rear master cylinder. I have a '72 750, that's kinda like (but really no where close) to a budget version of yours. I'm using a '79 Supersport front end, and silver comstars with a disk rear. I've been having trouble coming up with an idea for rear set mounts, that will work well with the rear master cylinder mount.

[TexasTwister250]

This might be a little off topic, but I must know how you mounted your rear sets, and the rear master cylinder. I have a '72 750, that's kinda like (but really no where close) to a budget version of yours. I'm using a '79 Supersport front end, and silver comstars with a disk rear. I've been having trouble coming up with an idea for rear set mounts, that will work well with the rear master cylinder mount.

The rear sets were a blast.  I have an 04 RC51 that I upgraded to some gold Sato rear sets (sweet).  So I had the stock one laying around for the last couple of years.  The way they mount worked out just right, they have a forward facing V shape that I positioned on the frame and centered on the swingarm pivot bolt so I wouldn't have any trouble getting it on and off.  I welded two 10mm setscrews to the frame and used a locking bolt into the recess to hold them on both sides. 

On the shifter side I had to flip over the shifter arm so it rides under the engine case, it is close but clears and I was able to adjust it to the right angle with the stock length connector. 

On the brake side I had ebayed a 07 GSXR 600 rear brake with master cylinder, but the mounting holes on the MC were about half the width of the mounting screw off to the rear sets.  And I decided I didn't like the mounting bracket cause it was on top of the brake and ugly.  So I ebayed an RC51 MC, got an 03 GSXR600 brake and mount, polished the mount.  This setup looks a lot better,cleaner and hangs under the SA, I really like it.  Then I had an extra steel braided line laying around from another project off of a Honda RS125 race bike, it was a perfect length.  Also I had a left over brake sensor from my Sato upgrade that I installed.  I used the reservoir off the 07 GSXR because it has a nice shape, it is square and thin.  I welded a tab to the frame and mounted it up.  Everything fits perfect and works better than I expected.  The only bummer is the kick starter hits the foot peg and the brake lever, so I removed it....    I really like the kick starter, but oh well that is about 4 more pounds the bike lost.

On your bike, I am not sure about other rear sets, but the RC51's are really nice and will fit the bike great if you give up the kick starter.

Speaking of pounds, I had really wanted to go with wire spoke wheels, may eventually make up a set and put them on.  But for now I really like the blacked out look of these wheels.   I was weighing the stock rear wheel and brake assembly...... 51lbs      The 08 GSXR600 wheel and tire assembly I mounted only weights 30lbs.  I didn't weight the front yet but I'll bet it will be a similar savings.  I can pick up the front or rear of the bike now, it must have lost a ton of weight.  The real challenge will be to not put it back on as I build it up.

[TexasTwister250]

Finally on the swingarm I had a machinist remove the shock mount chunk that was on the bottom of the arm for the original monoshock mount.  It only took about 5 min.  I had him also machine the mounts for the shock, I puchased the stock shockmount inserts and had a hole machined to the same od so it would be a press fit.  These were welded on.  After the first mock up, I had left to much material sticking up above the swingarm pivot so that it ws interfering with the chan.  See pic.  I went back to the machinist and had that surface machined down flush to the pivot on both sides then used 3/16 plate aluminium plates welded in to fill the openings.  Last to mount the SA, the diameter of the stock GSXR was a lot larger than the honda SA bolt, so I had inserts made to adapt the hole to the bolt diameter.  See pic.  My dimensions turned out to be a little tight on the OD so I would recommend reducing the OD by about .008" so it won't be so tight.  These were a bit pricey due to price of SS and the machine time to maintain the tight tolerances, I ended up paying $100 each for them.