Why? That might be your first question. The LC8 motor is a fabulous unit designed specifically for the task. I like it. I looked at purchasing a nice used 950 Adventure, but the size and heft was overwhelming for me--five eight, 150 lbs, 31" inseam, 66 years old. If (when) I drop it, I'd have to leave it. So I looked at the 690 KTM. Nice. Scarce. Expensive. But I didn't want a single. I already have a 2012 KTM 500 set-up for dual sport and it's great. I wanted a twin for more highway use than the 500 would tolerate. The Suzuki SV650 is a great little twin, the power (70hp, 47 ft lbs torque) made it a good candidate for an Adventure bike. The Wee-Strom is such a bike, but heavier than I'd like. Besides, I needed a project. But mostly, I'm a guy, and when you're a guy, it doesn't have to make sense. I've done stupid stuff before. Yamaha YZ450 motor in an R6 chassis.
So I started getting parts together with the hope of building some thing as light as I could without getting crazy and expensive. No titanium bolts. I checked it on paper, then with a scale mockup. As discussed in another post, I'd like to rotate the motor back about ten degrees. That may not be necessary, five degrees may work. So, this project is officially underway.
I found a clean-titled 2005 950 Adventure frame that had already traveled fifty-thousand miles and made a loop around Mexico/Central America. I scraped, brushed and Gunk'd it. Then I held my breath and started cutting off extra tabs specific to the Adventure, to clean it up and so my 990 SM-T tank would fit.
ahhhhh....getting really creative it's what they do out there in The Valley of the Sun during the summertime in order to keep from going crazy when it is TOO HOT TO RIDE
Weighed some parts today. The frame isn't light, 24 pounds. Incredibly stout, like it could survive a roll down a mountain. I'm sure many have.
The forks arrived from a dismantler in Canada. I took a chance on buying salvage forks off a 2008 990 Super Duke because they were cheap. Luckily, they fit fine after removing the steering wheel lock bracket from the frame. The problem with them is short travel, 5.3 inches, and the street orientation. I'm taking them by MotoLab in Phoenix to see if we can get another inch or more of travel. The parts fiche shows a spacer, so that may work. Besides, I could use the longer length to increase the trail, since a preliminary check showed a bit shallow rake. The good news is it looks like I am fine using a 19 inch front wheel, as the bottom-out distance axle-to-head is 14 inches. A 21 inch might even work, but I'm going nineteen.
The SV650 radiator will fit, but is too wide to fit the gas tank. I checked into getting it narrowed-up, but Myler's said they can remove tubes but not shorten them. So that means I could shorten the KTM radiator, so all good, if it works.
While I was wrapping up for the day, the motor arrived from Colorado, nicely boxed up. I'll get it open tomorrow, test the fit, and see if this project is gonna fly.
Eddieb--Sorry, no video of the 450 in the R6 chassis. I didn't keep it long. It wasn't fast enough, but it was a lot of fun. Sounded cool, too.
I know dirt bike KTM forks fit and they are very easy to modify for cheap to shorten the stroke. I had my shop lower mine for adv travel. Plus they are cheap and easy to get springs for weight. I sold a pair of 690 forks to a buddy and I know he isn't using them. They should be real close with spring weight too if you are interested. Somewhere in the $300 range. Have you checked clearance with a 19 or 21" wheel? Mine barely clears the rad with 11" travel but I'm guessing we havea different rake angle. Cool build I just love the marriage
I havea ninja 650 with KTM running gear. For the front end I'm running 450 exc forks. I had them at full travel but it's just too much. I had the whole bike lowered 1". But those forks are cheap on ebay and here couple hundred bucks. For front end I have it matched up to a normal KTM dirt bike hub, 320mm rotor and matching Braking caliber and matter cylinder. It's all the brake you need on these bikes. I have the same rotor setup on both 17/19 & 18/21 wheelsets so change over is simple brakes stay the same. I just don't know the compatibility of the SMR forks and brake lugs if they have to be radial etc. I know the dirt setups can be had for cheap and they are very easy to modify for heavier bikes like ours. My build thread has a lot of pictures and details, I've done this front end thing 4 times now so if you want advice I'm happy to share what works for me. I just don't want to intrude on your thread.