"A Bird in the Hand" take 2. DR650 Deadtail Bobber, now with a sidecar
- Thread starter Hurco550
- Start date
Maritime
Over 10,000 Posts
LS 650 is basically the same lump prettied up I think.
unfortunately, the LS 650 and DR 650 share almost nothing, neither in design or parts. It never made sense to me.
Tanshanomi
Active Member
Modern Japanese engines are so compact, front-to-back, that they usually don't look good in pre-unit Britbike frames. There's so much extra space that they end up swimming around in it like a kid wearing Dad's suit.
DR800 in BSA A10 frame:
Maritime
Over 10,000 Posts
Huh, I thought they were similar for some reason. Oh well.
This was a big challenge and a large part of why I ended up building a frame from scratch. The DR frame doesn't lend itself well to a hardtail, and most other frames have far too long of a cradle. If I had to do it over again, I would have actually made the down tube from behind the motor to the spine about 1.5" closer to the back of the engine. It ended up giving me a bit of space to mount the cdi and solenoid though so all's well that ends well.
Tanshanomi
Active Member
That paste-up was the original visualization for the Manki, an LS650 in a Norton Featherbed frame. The guy who built it did a great job of disguising the engine's length with a faux "primary case" enclosure on the left and strategic battery box placement on the right. Unfortunately, that's not a great solution from an engineering point of view, because the countershaft sprocket ends up so far from the swingarm pivot that maintaining proper chain tension with any sizable amount of rear suspension movement becomes rather problematic.
Rider52
Over 1,000 Posts
Proportion is important. Back in the 70s most of the rigid aftermarket frames were based on the Harley rigid frame proportions. Too much stretch for a Honda 350 or 450 twin made for a large open area where the HD transmission and oil tank resides. Some creative builders solved this in various unique ways to produce stunning motorcycles. The average garage folks just lived with it. Levi be glad you added the extra at the down tube behind the engine. The frame proportions look great and it allowed for necessary mounting points. Years ago a friend built a rigid frame for a Honda XL350. He wanted it tight and he did a great job of building the frame but the overall frame length was short and it rode like crap. He coupled this was a short rake which made the bike handle like crap too. Shortly after he finished it, he broke it down and cut up the frame. Kind of a shame as it was a good looking bike and would have made a great display in someone's office.
JerryAssburger
Been Around the Block
...agreed! It seems like ANYthing dirt-bike related is over-the-top over-priced. I was even looking for any sort of thumpers, and even the LS650s (with their goofy belt drive) are pricey hard to find. I even searched for Buell Blasts.... nope. ATCs...? Not so easy. I AM in a very "rare" place for decent two-wheelers, though. That's why I think those Shineray engines on E-bay might be a Thing- especially if they branch out.
I have said a few times that if I were to do it all over again, I'd make it a bit shorter. I wanted to take out an inch or so between the engine and down tube and about the same between the down tube and rear axle. That said, this thing really does handle well. I know that sounds like a cliche that everyone that builds their own bike would say, but having run it up to 80 mph or so (not sure I have plans to go much over than that) with no shakes or wobbles of any kind, and when you let go of the bars it tracks dead straight, I'm happy as a horse. Somewhere half way through this project, I did take 1.25" or so out of the wheel base by drilling new holes in the axle plate and trimming them down. I am glad that I shortened it up at least that much.
@irk miller has said that "there is no machine abused worse than a dual sport that is treated like a dirbike". I think that has much to do with the lack of ability to find big singles lumps in good shape. Once they are used up to the point that the engine comes out, they are done for.
I got to ride the bike in to the school for in service. I finally got the oil leak sealed up and the rear brake sorted. I can get right at 86 miles to the tank, which will take some planning if i do any "longer" rides. In a straight shot, I'll be ready fit a break at that point anyways.
My boss took it for a rip. He was a fan.
There was a bit too much rain in the forecast for a ride in for the students first day today, but I think I'll go for it tomorrow. The ones that worked on it are excited to see it finished.
My boss took it for a rip. He was a fan.
There was a bit too much rain in the forecast for a ride in for the students first day today, but I think I'll go for it tomorrow. The ones that worked on it are excited to see it finished.
JerryAssburger
Been Around the Block
How cool! You made their day(s)!
Looks amazing. It's just heavy.
I'm just glad its lighter than a certain 350cc Yamaha I know of....
Working through a few bugs after a couple hundred shakedown miles. The seat ended up being mounted a little too low in the rear, and with my 240 lb self along with my backpack to go to work, the seat was hitting the fender rib. On top of that, without much of a lip on the back, the pumper carbed motor was pretty constantly trying to yeet you onto the fender on acceleration and my arms were getting tired from trying to hang on haha I made up a couple of quick spacers that brought the back of the seat up about an inch. It's been raining all afternoon, so I haven't gotten to do a test ride, but I think it should solve the issues.
