ok guys...me and my little brother have been SLOWLY gathering parts for a build..and im not about to start a build thread just yet ...maybe this isnt the right place to post this...but i cant see a better place to even consider posting it as it will end up in here sooner or later HOWEVER...i do need the help of the crazys who spend there time in here i need to come up with a transmission or ideas of how to setup a transmission.... the design of the bike will loosely be saltflats bobber 50s early 60s ish...the engine..well...you wont know it but its from a german micro car a lloyd 600.....air cooled 4 stroke over head cam 600cc twin(not v)...now here is the problem..what do i use for a trans?..it was designed to be a FWD so i "could" use the stock 4spd but its a little bit bulky..and id have to weld up the dif but then that will also make for some very CRAZY shifting being a 4spd with reverse...and im sure the gearing would be crap but that could be ran thru a secondary reduction/overdrive as it was designed to push a 1600lb car to 61mph so ...im simply going to say...HELP :huh...really dont even want to look at hog stuff but....if thats the only option lay it on me dont bother saying use another engine..this bike WILL be built around this motor PERIOD...so im looking for any cobbling ideas of a trans
Some of the pre-unit stuff might work but we need a little more info, what is the configuration of the engine? Where is the output shaft?
ill go digging thru my pic's..but really imagine taking one side off of a VW bug engine and putting an oil pan in its place...thats basicly what im working with...no output shaft just a flywheel and clutch...engine will be mounted in traditional form..exhaust exiting the front carb to the real output to the left (shifter side of a bike) hears a similar shot of the engine
I know that one - my dad, close to 84, had one once! Where did you get that one? If you have to think of cooling, it has to be mounted like a traditional parallel twin: Across the frame! So a gearbox from a HD might be an idea, and then a chain/belt-drive as final?
actualy i have a few of them..3 engines 2 cars..one of the cars is totaly alfa running gear suspension etc anyway it needs to be cooled sooo its gotta be mounted traditionaly...also chain drive is a REQUIREMENT due to the style we are after....ugh a HD unit eh..well there goes the budget...any other options?
Why don't you speak to a few transmission specialist companies? In the UK we have Quaife and Xtrac who make racing car gearboxes, who may have something suitable or they may know of someone else who does. I think that if you close your mind down to just bike gearboxes then you're looking only at pre unit stuff, so Harleys and old british bikes is about the limit. Not sure who there is in the US, but surely Google can find someone making a version of what you want - but I do think you need to widen your scope a bit. If you accept something slightly less than ideal you may be able to pick from three solutions but if you seek only the perfect solution you may never find it.
You could always dissasemble ( read: grind off, saw off ) some traditional motorcycle 5-6 spd gearbox that has separate oil chamber for the gearbox, and manufacture the mounts to fit your engine. Most of kawasakis and other Japaneese bikes have the sprocket output on the left side so you could research that for start. It would also really be cool if you weren't limited on chain final drive, you could use a cvt transmision, as someone before me mentioned. There are tons of really cheap maxy scooter variomatic drives that could be found for 50-100 bucks used. You could try with Piaggio Beverly 500 for example, it is designed to take a lot of torque, and can be completely dissasembeled from the engine, and could bolt on to your output with some adjustments ;-) It is left side mount and it is relatively loong, but you have take into consideration that it is designed for the 14" rear wheel, but could also fit 16" with slimmer tyres Good luck, and keep us posted of your progress. cheers a.
see now THATS what i wanted to hear...about cutting down a traditional moto trans..and in the style he wants the bike..the more "scavenging" we can do ...the better.....but im at a loss on what engines might have a good setup to do this as for a cvt/automatic..NO..must be a manual trans...weve even considered welding up the diff from the stock trans and modifying an output shaft for a sprocket...far from ideal nit its an option we are willing to entertain.....shifting would be a chore tho im not closing my eyes to other possibilitys ....but there ARE limitations due to the STYLE of the build which means NO modern trans(and due to cost as few "new" parts as possible with the exception of reliability as it is a bobber)...as much of the bike as possible needs to be at newest early 80s....and lets face it..most of that stuff hadnt really changed in 20 years
Harley 5 speed trans popular, inexpensive, strong. Set up for chain or belt primary, and secondary. clutch on trans. Can be dry or wet. Baker has new 5, 6 and maybe by now 7 speeds..Also reverse if you are interested. Otherwise, BMW or Guzzi will get you the rear drive too in one compact package. Rod
Apart from 2 strokes, I don't know of any "unit construction" bike that has a separate gearbox chamber, and the 2 strokes tend to have a fairly narrow rev range and low torque. Also they are not available in many variants making it pretty much impossible to swap ratios wiith other bikes using the same basic architecture. If you can machine down an existing 2 stroke crankcase and retain enough strength whilst making the gearbox the correct size and shape to fit your engine, (and I'm not sure all that's possible), will you end up with suitable ratios and torque capabilities for your new application. A different option would be to use the gearbox from a BMW or Guzzi as that can at least be separated from the engine, but they use a different architecture as they are intended for longitudinal installation between the engine and the shaft drive, and you have stated that you want to use a chain. I also think the general arrangement of these gearboxes does not really lend itself to the shape of your engine. Remember that its not just a case of joining the shafts together - it all needs to be packaged within the confines of the bikes wheelbase and narrow enough to allow sensible cornering. A bit of advice, which you can choose to take or ignore - its entirely up to you - is to think through the whole project very carefully indeed, and get your eyes and your tape measure on every part that you consider suitable before you actually buy any parts. I do think that you will struggle to find parts that work well together, and that machining it up yourself and mounting it all in a frame will inevitably end up making the bike 30% bigger and heavier than if it were manufactured by one manufacturer who would optimise parts as they went along and make sure that everything was designed to fit and work together, rather than being persuaded to fit and work together. If you just buy a gearbox that ought to work with the self belief that "hey I can make it all work ok", then you may well end up in your own personal debt crisis when parts do not end up working how you'd like them to, and the replacements that you end up buying are not really any good either. Remember that any parts you buy and then alter by machining will have no resale value whatsoever. It depends how you see it. If the process of getting there is more enjoyable than the bike you actually end up with, then go for it. I have tackled projects of my own that gave me immense satisfaction despite not ever getting finished, but if your goal is to have a competent working bike at the end, then do consider just going out and buying one as it will be cheaper and better in the long run. Now please get yourself all fired up and prove me wrong.
What are the horsepower and performance characteristics of the engine? And along with what sort of performance expectations do you have of the complete motorcycle. This question is one that crops up all the time in online build forums. People want a simple light weight unit transmission that can be used for making; Go Karts, Motorcycles, Lawn Tractors, Boats. They want it inline, compact, and cheap. Unfortunately the animal does not exist readily on the market. In these types of engines your options for transmission falls into, belt/variator cvt drives, direct drive from chain sprocket, or engines with build in transmissions such as ATV's Dirt bikes etc. I have looked into getting chinese manufacture of a small 4 or 5 speed shaft in shaft out inline transmission to utilize in place of a jackshaft. But so far have not found it feasible. Some lawn tractors however are promising, many have "transaxles) and I have looked into removing the differential, machining the case back and installing a spool with one output shaft and a gear. These transmissions are usually belt fed, and have 3 gears and reverse. You could sort of suicide shift the unit. But only a few have an input shaft that is horizontal instead of vertical, and only a few are non-hydrostatic.
the more i look at all this more more it seems like a Hd or indian style unit makes the most sense ive actualy got a lawn mower 4spd chain in and out unit that i had built a gocart from with a yamaha 400 twin......it actualy held it just fine im not afraid of the project..and the fact is ive made all the measurements except a trans..its currently the ONLY wild card..wheels will be dual sport spokes for the simple fact of me and my lil bro both like the size, look and tire selection...as well as the DRUMS of the early 80s stuff cost wise..the trans since its the only thing besides tank and tires that we dont currently have or have awaiting pickup will be the only thing with any realy monitary value attached to it ragtoplvr thanx for the hint on looking to baker as well
Google" Tularis". The Tularis was a handmade roadracer using a Polaris snowmobile motor in a barely there chassis and transfering the power through a transmission made fron the gearsets of a 996 Ducati in special made carbon-fiber cases. It was the work of a guy I met in the 80's when he was racing a 750 Norton in Sportsman 750 class at the AHRMA races. Now he's Dr. Rob Tulie. He was fast on the track but, not as fast as his mind was working. He also made a short-stroke crank for the Norton causing AHRMA to ban short-stroke cranks in Norton for Sportsman 750.Another of his bike was the Tulda. It was a CR 500 Honda mx motor in a self-made trellis frame to run in theS.O.S. two stroke class. It's a bit out there to suggest you build carbon-fiber tranny cases, but, it is possible. I think I'd lean toward BSA,Triumph, Norton or H-D non unit transmissions. -
ok that....that just sounds BADASS to no end.......but i think ill stick with something atleast partialy premade...but that sure would add to the wow unique factor
turn a bmw/guzzi/goldwing gearbox sidways, grind off the bell housing, mount a multi plate bike clutch dry on the gearbox input shaft, ribbed belt forward to the engine output, sprocket on the gearbox output shaft to the rear wheel. many hours of struggling, or a hd gearbox.
