Building an ST1300 from the ground up.

Update time! The subframe is still not finished. Life 'n all that, you know? I have a friend with a mill making me a top triple to go with an MX Bonz bar clamp I got. After searching eBay almost daily since this thread started for a radiator that wasn't $7 less than a new one (ahem- suncoastcycles), I found one, along with the fans, a clutch master cylinder with lever, a left handlebar switch, and a big 'ole box of nuts and bolts and miscellaneous hardware from a parted out ST1300. My junk hardware drawer runneth over.

Also, I was doing some unrelated research via microfische and eBay and discovered a potential parts compatibility for this project that will blow your minds. I don't want to go into it and get your hopes up, but I have some parts on the way so I can test my theory. If what I believe to work will work, it's going to take this project to a whole new level. Stay tuned... this discovery might be huge.

Really.
This and the PR 4's..

indeed. I woke up thinking about what I may have stumbled upon.

I'll take a guess ...

The same software runs the HondaJet as runs our ST1300s. No wonder they want to fly. Sadly, this also means inevitable stuck thermostats in the HondaJets are "operating within normal specifications".

Close?

Close. The front end swaps over to the HondaJet. The Pan Weave (Jet Weave in this case) becomes exponentially more problematic, however.

Don't keep us in suspense!

I'm in as much suspense because I'm waiting on parts to verify fitment!

Here's a hint: If it works, it's something that I think a lot of you will be interested in doing, especially if you go through a lot of tires. I guess that's not much of a hint, huh?

Damn, you guessed it! I'm going to see if an OEM 17" tire from a Civic fits.

I was gonna guess single sided swing arm off a Gold Wing.

What size exactly, Mandrake. a 175/70/17 would be perfect if you can find that size. Can't get one like that in the USA. (<edit, add> Oops, never mind, that's the best size for 1100. Most folks are running a 205/55/17 on the 13s I think.)

Single sided would be way cool,,,, wider would be very cool, as it would allow more choices for the 1300 guys. Either would be a step up so no more grinding was needed for the Goodyeat TT.

Parts will be here Thursday, and if they're compatible, it'll be another week or two 'till I get the rest and make them functional. Once that's happened, pictures and info will follow.

A delay in shipping won't have the parts in question here until Tuesday. In the mean time, some gee- whiz info: The bottom diameter of the ST1300 stem is exactly the same diameter as an '06 GSX-R600 stem. The bike will be going out some time this week to a local welding shop so they can modify the RC51 subframe to bolt to the ST1300 frame since I'm not set up to weld aluminum.

Quick shot of my fat *** on the bike to demonstrate the upright ergos. I was able to use the spare triangle side engine mount braces I have to bolt the RC51 subframe to the top subframe mount on the ST frame, and am using a 2X4 to support the lower portion as seen in the picture. First time sitting on the bike, and I'm really digging it. It feels very short coupled and upright, very close to what a Ducati Monster or MV Agusta Brutale feels like.

Hot knees?...hum....

Sabre- Not pictured is my riding gear. I'm not a squid and wear about 20 lbs. of dead cow when I venture further than the end of my driveway. My knees won't get hot.

Mike- The bars, top tree and bar clamps are temporary mock up parts and are unfit for photography. A friend is going to machine me a billet top tree and I'll be using an MX BONZ bar clamp with my Driven 1.125" carbon fiber bar I have for it. When I get that detail sorted, I will certainly take pics. Once it's done and painted (probably spring time), I'll have some good, high- res shots taken. I already have the perfect location for the photo shoot.

Well, the parts in question showed up, and we all can consider my hopes and dreams crushed. I feel like I'm back on active duty and was just told we're coming in on Saturday because someone on a different shift in a different shop screwed up.

So here was the grand master secret plan... GL1800 swing arm swap. Yup. The pivot bearings and a whole bunch of other stuff all cross referenced between the two bikes. As best as I could tell from measurements and guestimates I was able to make by looking at pictures and parts fisches, it would work with minimal effort. Turns out, the GL swinger is about an inch wider than the ST, and would require a section cut out of the middle and the two halves welded back together. Interestingly, the GL swinger is only 1/2" longer than the ST, so depending on how much slip engagement is made by the ST driveshaft in the ST u-joint, that aspect may be a compatible match; if not, a driveshaft shop could add the 1/2" very easily. Also, the retaining circlip on the rear of the ST driveshaft is the same part number as the GL driveshaft, so I believe that the ST shaft would work with the GL final gearbox. The shocks are different; the ST is a direct drive where the GL has a ProLink like the sport bikes, so a tab would have to be welded to the top of the GL swinger. Considering the GL swinger is made to support 900+ lbs, I strongly suspect that there's enough material there to do this mod safely, given the welding is done by a competent and certified welder.

Since I picked up the bare GL swinger for $28 shipped, I'm not too hurt about it. At some point, I'll probably throw it up on the band saw and cut it apart to see how thick the casting is, and bring the parts to my welder to see what he thinks about making it work. For now, the project soldiers on with the normal ST1300 rear end.

Here's what I'm sorta maybe thinking about for exhaust. I'm curious if any of you pick up on the nod to two motorcycle manufacturers that battled it out in the WSBK back around the turn of the century...

Mandrake said:

Sabre- Not pictured is my riding gear. I'm not a squid and wear about 20 lbs. of dead cow when I venture further than the end of my driveway. My knees won't get hot.


...

Click to expand...

I've ridden in heat (115F) with chaps on before an noticed how well the leather kept the heat from my legs, much better than my current riding pants...4:

So let us know how well that works out for you!

I had a feeling you were playing with a gl18 swingarm. That's a bummer, but like you I suspect it can be made to work.

Sent from my SPH-L710 using Tapatalk 4

Jason- here's some more of my thoughts on the GL swinger...

Since an inch would have to be taken out of the swinger to make it fit between the ST frame, the hub flange would move to the left 1/2" relative to where it *should* be on the GL. That's not too big of an issue because of a wheel swap I had in mind...

The GL1800 uses a 16X5 wheel. Good luck finding anything remotely sporty to fit that. I already looked; it's all cruiser stuff. Good tires, but not what I'm after, and not what I think would fit the nature of the ST in general. Then again, some of you guys are putting car tires on these things, sooo... Anyway, a 16" wheel won't cut it for me. The Rune wheel is a 17X5.5 and would be perfect, but it's stupid expensive new, and nigh unobtainable used. However, the VFR800 wheel is 17X5.5, much more attractive than the Rune or GL wheel, and is much more common- I've seen them for $150 on Ebay. The kicker is that it's a four lug. BUT! It has much more offset. Think of it more like a wheel on a FWD car, and the GL/ Rune wheel like a RWD car's wheel, if that makes sense. I don't have measurements for any of this, but looking at a VFR swing arm in person vs. a GL swing arm in person, I think there's enough offset difference to make a VFR800 wheel fit on the GL swinger with a five lug to four lug adapter between the two.

Over the winter, I'll probably revisit the GL swinger swap, and if it's a viable option to cut it down and weld it together, I'll look more in depth at the VFR wheel swap, too. For now, it's all speculation.

There are guys that really make a Wing dance in the twisties on a CT. If performance is the question with a17 inch wheel I bet you would be pleasantly surprised.