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Here's a project I have been busy with (still am) and want to share with you. Lots of pics for the interested. It will be familiar to some of you guys as I copied most of it from the UK site, which I updated daily.
Last month a friend of mine, whose hobby is building frames, and myself have been busy in building a replica frame late 70's beginning of 80's endurance racer style. To do that i had to travel 200 miles to Friesland in the north of the Netherlands with in the back of the car: 1 engine, 1 xschop chaindrive, 1 rear wheel, 1 set of rsd front forks, 1 exhaust and a handfull of monoshocks...
A new one off frame + swingarm was to be made within a couple of weeks for my long dreamed of a classic endurance racer replica whatever..
What will it look like? Well it will be a mix of a 70's Godier Genoud Kawasaki endurance racer and a 80's Motoplast frame (Kwacker, Laverda). I love these racers as I have been visiting these endurance races in those days when it was still possible to walk through the pits. Lots of ingenious technical solutions coupled with gorgeous styling and big horsepower in comfotable frames. As Yamaha was not exactly overly busy in these days it will be a bike that Yamaha should have built (in my humble opinion). Still had that spare ex-turbo engine lying around so that worked out well.
For the people who don't know the above mentioned bikes: this is a GG kwacker from the 70's:
This is a Motoplast Laverda:
This is a GG frame (seat and tank are monocoque):
This is a Motoplast frame:
Frametubes will be thicker though as I think they look tiny. They worked well however in those days. No tubing under the engine. I will definitely go for the monocoque construction, keeping the frame low and short. Looks nice and tidy. It will also get a one off swingarm: I am thinking of a GG lookalike but with a side mounted monoshock although it will be difficult to connect it to the back of the frame
september 24th 2009
ready for transport. Scruffy ex-turbo engine with shiny chaindrive:
first picture of the mockup...
november 20th 2009
Second pic arrived today.. took a while because the guy just extended his garage to double size..
old wheelbase 1545mm, estimated new one 1440mm, steering head angle was 60,5 degrees, new 66 degrees from horizontal
november 22nd 2009
Tubing for the frame itself will be 32x2 mm (smaller than what he normally uses), for the swingarm 27x2mm. As the front wheel fitted in the end will be a 17" instead of the now fitted 18" , wheelbase will shrink another 20mm to 1420mm. Still looking for that wheel however..
Next pic show the RC Engineering collector fitted to check clearance.added
This frame will not use the two lower front engine mounts (I don't like the looks) but only the upper front ones and the rear ones (solid ones, no rubber). Two extra engine mounts will be made and connected to the upper part of the rear of the engine: one bolted to the chain drive on the left, one bolted instead of the crankcase cover on the right. Alsointhe upperpicture is the solid solution for the front engine mounting , this 30mm pipe has the same diameter as the inside of the engine mount and will be bolted to the frame and stays with the engine when lowered.
November 23rd 2009
Frame will be 31cm wide where the swingarm mounts, so a 200mm wide rear tire is a possibility.
Kickstarter is a must, so still waiting for an answer if the frame is not too wide at the right side..
Kickstarter is a must, so still waiting for an answer if the frame is not too wide at the right side..
november 25th 2009
Well, frame was too wide. So cut up and made new, it is now 29cm wide. Still possible to use a 200mm tire if necessary in the future.
Communicating by email is a bit difficult as it turns out. His next step has to be to cut again as it is too high. He already thought it would be too high as he is still thinking in streetfighter lines. I think the correct hight is the same as the intake ports, still good to mount the rear shock I think. I want it as low as possible. Have to wait though as he is asleep now after working last night. He is a proces operator.
november 26th
Well, frame was too wide. So cut up and made new, it is now 29cm
.
In the meantime i'm having problems in the wheel department. As I cannot find a matching front wheel to the dymag 5-spoke in the pics I obtained two period Marvic Magnesium wheels. The rear wheel I bought in France ( a small regional "a vendre"site) for a ridiculous price. It is a 6x18" wheel. A 5.5x18" wheel would be better but it is a start.
A marvic front wheel was handed to me by a friend and it looks horrible. I had it checked and it turns out it has a crack in the rim and one of the spokes is oxidized completely. Aluminum oxidizes on the surface only, magnesium oxidizes within the material, unvisible to the eye. So this wheel is good for the bin.
Next update. I asked him to lower the headstock in comparison to the rest of the frame. That way I can ride with clip ons on top of the upper plate. It also makes it easier to place the front frame tubes.
:
I Don't like the looks of that either, so I asked him to try and get the same look as on the GG and MP frame in front of the cylinderhead were all tubes come together. As there is no room for the horizontal tube from ft to right nor for removing the outer spark plugs he went back to the drawing board. Another friend stepped in with a 3D drawing in order to help: This is the first try,based on his own bike ( a Moto Martin framed ZX750).
I like the look of that but cannot imagine how the rest will look when added. so ...........second try after an hour ... all based on the first pics of the GG and Motoplast frames..
Now we all could visualize everything alot better and In order to achieve my request he altered the way the tube runs along the side, a lot higher now.
Way better!
And from the rear..
Now this is definitely going in the right direction.
november 26th 2009
Q said he needs info on the shock as this happens without one hahaha
Great program!
Because i want the frame tubes in front of the engine the same as the GG, conclusion was there is not enough room for the tubing AND the possibility to remove the valve cover. I suggested to make the first tube V-shaped, but it was not enough..
After that I suggested to change the wheelbase and the steering head angle to less extreme values. That helped a lot. He also tilted the engine a bit backwards. Now there was room for the extra tubing. Only remaing problem was that the sparkplugs could not be reached anymore. So the tube went upwards, meaning no longer a straight line from headstock via the front tube to the rear. I can live with that as the GG does not have that either.. This is the end result so far:
mmmmm, that's less than we had yesterday
november 27th
He is busy early ..
That's better!
Last month a friend of mine, whose hobby is building frames, and myself have been busy in building a replica frame late 70's beginning of 80's endurance racer style. To do that i had to travel 200 miles to Friesland in the north of the Netherlands with in the back of the car: 1 engine, 1 xschop chaindrive, 1 rear wheel, 1 set of rsd front forks, 1 exhaust and a handfull of monoshocks...
A new one off frame + swingarm was to be made within a couple of weeks for my long dreamed of a classic endurance racer replica whatever..
What will it look like? Well it will be a mix of a 70's Godier Genoud Kawasaki endurance racer and a 80's Motoplast frame (Kwacker, Laverda). I love these racers as I have been visiting these endurance races in those days when it was still possible to walk through the pits. Lots of ingenious technical solutions coupled with gorgeous styling and big horsepower in comfotable frames. As Yamaha was not exactly overly busy in these days it will be a bike that Yamaha should have built (in my humble opinion). Still had that spare ex-turbo engine lying around so that worked out well.
For the people who don't know the above mentioned bikes: this is a GG kwacker from the 70's:
This is a Motoplast Laverda:
This is a GG frame (seat and tank are monocoque):
This is a Motoplast frame:
Frametubes will be thicker though as I think they look tiny. They worked well however in those days. No tubing under the engine. I will definitely go for the monocoque construction, keeping the frame low and short. Looks nice and tidy. It will also get a one off swingarm: I am thinking of a GG lookalike but with a side mounted monoshock although it will be difficult to connect it to the back of the frame
september 24th 2009
ready for transport. Scruffy ex-turbo engine with shiny chaindrive:
first picture of the mockup...
november 20th 2009
Second pic arrived today.. took a while because the guy just extended his garage to double size..
old wheelbase 1545mm, estimated new one 1440mm, steering head angle was 60,5 degrees, new 66 degrees from horizontal
november 22nd 2009
Tubing for the frame itself will be 32x2 mm (smaller than what he normally uses), for the swingarm 27x2mm. As the front wheel fitted in the end will be a 17" instead of the now fitted 18" , wheelbase will shrink another 20mm to 1420mm. Still looking for that wheel however..
Next pic show the RC Engineering collector fitted to check clearance.added
This frame will not use the two lower front engine mounts (I don't like the looks) but only the upper front ones and the rear ones (solid ones, no rubber). Two extra engine mounts will be made and connected to the upper part of the rear of the engine: one bolted to the chain drive on the left, one bolted instead of the crankcase cover on the right. Alsointhe upperpicture is the solid solution for the front engine mounting , this 30mm pipe has the same diameter as the inside of the engine mount and will be bolted to the frame and stays with the engine when lowered.
November 23rd 2009
Frame will be 31cm wide where the swingarm mounts, so a 200mm wide rear tire is a possibility.
Kickstarter is a must, so still waiting for an answer if the frame is not too wide at the right side..
Kickstarter is a must, so still waiting for an answer if the frame is not too wide at the right side..
november 25th 2009
Well, frame was too wide. So cut up and made new, it is now 29cm wide. Still possible to use a 200mm tire if necessary in the future.
Communicating by email is a bit difficult as it turns out. His next step has to be to cut again as it is too high. He already thought it would be too high as he is still thinking in streetfighter lines. I think the correct hight is the same as the intake ports, still good to mount the rear shock I think. I want it as low as possible. Have to wait though as he is asleep now after working last night. He is a proces operator.
november 26th
Well, frame was too wide. So cut up and made new, it is now 29cm
.
In the meantime i'm having problems in the wheel department. As I cannot find a matching front wheel to the dymag 5-spoke in the pics I obtained two period Marvic Magnesium wheels. The rear wheel I bought in France ( a small regional "a vendre"site) for a ridiculous price. It is a 6x18" wheel. A 5.5x18" wheel would be better but it is a start.
A marvic front wheel was handed to me by a friend and it looks horrible. I had it checked and it turns out it has a crack in the rim and one of the spokes is oxidized completely. Aluminum oxidizes on the surface only, magnesium oxidizes within the material, unvisible to the eye. So this wheel is good for the bin.
Next update. I asked him to lower the headstock in comparison to the rest of the frame. That way I can ride with clip ons on top of the upper plate. It also makes it easier to place the front frame tubes.
:I Don't like the looks of that either, so I asked him to try and get the same look as on the GG and MP frame in front of the cylinderhead were all tubes come together. As there is no room for the horizontal tube from ft to right nor for removing the outer spark plugs he went back to the drawing board. Another friend stepped in with a 3D drawing in order to help: This is the first try,based on his own bike ( a Moto Martin framed ZX750).
I like the look of that but cannot imagine how the rest will look when added. so ...........second try after an hour ... all based on the first pics of the GG and Motoplast frames..
Now we all could visualize everything alot better and In order to achieve my request he altered the way the tube runs along the side, a lot higher now.
Way better!
And from the rear..
Now this is definitely going in the right direction.
november 26th 2009
Q said he needs info on the shock as this happens without one hahaha
Great program!
Because i want the frame tubes in front of the engine the same as the GG, conclusion was there is not enough room for the tubing AND the possibility to remove the valve cover. I suggested to make the first tube V-shaped, but it was not enough..
After that I suggested to change the wheelbase and the steering head angle to less extreme values. That helped a lot. He also tilted the engine a bit backwards. Now there was room for the extra tubing. Only remaing problem was that the sparkplugs could not be reached anymore. So the tube went upwards, meaning no longer a straight line from headstock via the front tube to the rear. I can live with that as the GG does not have that either.. This is the end result so far:
mmmmm, that's less than we had yesterday
november 27th
He is busy early ..
That's better!
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