Newbie CB750 Cafe Project
- Thread starter ljonny18
- Start date
Hoosier Daddy
Earache my eye...
Filling with lead is a lost art... nice!
New parts: I ordered some new gaskets (this time the correct parts) so that I can hopefully (eventually) get the motor back together
When putting the valves back in, I managed to break one
therefore one is still pending. The replacement:
and some additional bits and pieces that I require:
When putting the valves back in, I managed to break one
therefore one is still pending. The replacement:
and some additional bits and pieces that I require:
Back to the never ending story of my tank... I think next time I will spend a bit more money and get a decent tank as a starting base. I thought as the plan way to modify the tank, an old battered one would suffice, however I am paying for this now. The tank is full of dents, some so small they are hardly visible. I have pulled out what I can the larger ones and prepped / blasted the smaller ones for further filling
As I mentioned and showed in a previous post, I used metal rods to fill the wholes instead of using filler etc.. mainly just to test and try the method in comparison to filler as I have heard good thongs about it and also as its a stronger finish etc. The rods are basically a tinning solution that contained and when heated up melt into a fluid solution that can be worked with. Since my last post I have however improved the process. I was experiencing problems on some parts of the tank where the solution was not mating well with then tank (although blasted and cleaned). I looked further into this and bought a non corrosive zinc chloride based paste which I applied to the tank before filling with the rods creating a v-good bond between the two:
Its really easy and good, basically apply the paste:
Heat it up:
And wipe it off:
Leaving a perfect surface where the lead filler can be nicely applied to
This is all cool and much fun, although the next step is basically sanding, sanding and more sanding which is not much fun : ( Here is a small one I completed as an example:
Looks good:
Its really easy and good, basically apply the paste:
Heat it up:
And wipe it off:
Leaving a perfect surface where the lead filler can be nicely applied to
This is all cool and much fun, although the next step is basically sanding, sanding and more sanding which is not much fun : ( Here is a small one I completed as an example:
Looks good:
Needed a break from dents so decided to finally get the SOHC tank fitted and sitting how I want it on the DOHC frame. Started out with the original tank to get an idea of spacing and how much room there is to play with re the motor etc...
Also added the yokes and bars to make sure they do not hit the tank on full lock - this was a worry of mine as I thought they would, and id have to modify the rubber mounts to move the tank back a couple of cm however they do not and there is full clearance on both sides
Further modification required - the tank still needs to sit a few cm lower at the back and the tank bracket holder catches on frame in the corner, so they needed to be trimmed:
Once trimmed the tank sat lower which is good, but bade contact again from other parts underneath, therefore further heating and modification was required :S
After a few hours the tank is sitting at the required / wanted height and is making no contact with the frame result ! However all the modification has appeared to dis-shaped the tank a bit - it is now wider that before. We simply compressed it a cm and its back and square again:
This is quite a step for me... from the start I wanted to use the older tank on the newer frame and now this step is almost complete. The tank is sitting how I want it :
I have learnt a lot getting to fit this tank, and know that next time I will do it differently The better way would have been to simply cut away the problematic areas and weld them back with sheet metal etc rather than heating up the underside of the tank and modifying it with a hammer however you live and learn and this is the whole point of this project !
Also added the yokes and bars to make sure they do not hit the tank on full lock - this was a worry of mine as I thought they would, and id have to modify the rubber mounts to move the tank back a couple of cm however they do not and there is full clearance on both sides
Further modification required - the tank still needs to sit a few cm lower at the back and the tank bracket holder catches on frame in the corner, so they needed to be trimmed:
Once trimmed the tank sat lower which is good, but bade contact again from other parts underneath, therefore further heating and modification was required :S
After a few hours the tank is sitting at the required / wanted height and is making no contact with the frame
result ! However all the modification has appeared to dis-shaped the tank a bit - it is now wider that before. We simply compressed it a cm and its back and square again:
This is quite a step for me... from the start I wanted to use the older tank on the newer frame and now this step is almost complete. The tank is sitting how I want it :
I have learnt a lot getting to fit this tank, and know that next time I will do it differently
The better way would have been to simply cut away the problematic areas and weld them back with sheet metal etc rather than heating up the underside of the tank and modifying it with a hammer however you live and learn and this is the whole point of this project !Next step was to create a bracket to securely attach the tank top the frame.
The tank has mounts at the front that connect to the rubber mounts on the frame. I did not have to change the fram mounts or the tank brackts as this was already aligned perfectly, all I had to do here was replace the DOHC mount rubbers with SOHC rubbers as they are smaller and will therefore fit the tank brackets etc - so this was v-simple, however the back was not quite so simple:
We used the original SOCH rubber at the back and made a holder for it that could be attached to a custom bracket and in turn attached to the frame :S here goes:
The rubber:
The holder:
The bracket:
We then welded a nut to the bottom of the frame to screw the bracket into:
finished:
A securely fitted tank
The tank has mounts at the front that connect to the rubber mounts on the frame. I did not have to change the fram mounts or the tank brackts as this was already aligned perfectly, all I had to do here was replace the DOHC mount rubbers with SOHC rubbers as they are smaller and will therefore fit the tank brackets etc - so this was v-simple, however the back was not quite so simple:
We used the original SOCH rubber at the back and made a holder for it that could be attached to a custom bracket and in turn attached to the frame :S here goes:
The rubber:
The holder:
The bracket:
We then welded a nut to the bottom of the frame to screw the bracket into:
finished:
A securely fitted tank
Things are starting to come slowly together so I started to play about with some ideas for the side pods / battery cover etc using an old computer case... will have to give this some more thought
Then the little man came to inspect what was going and wanted to play so that was the end of a productive day
Then the little man came to inspect what was going and wanted to play so that was the end of a productive day
Next step to avoid sanding was to create a pressure test system for the tank. All the beating and modification has left some cracks in the tank that need some attention. I fixed up all the ones I could visibly find but this is not (nowhere near 100% proof):
Blocker for the top (entry cap) complete with bottom (underside) holding bracket and entry (gauge tube):
and for the bottom (petrol tap):
Let the testing commence:
Result: Failed miserably - back to the workbench ! Although to be fair the air leaks where from sections of the tank that were not touched and where you would least expect them (top of the tank in good undamaged areas), the underside appears to be sealed up nicely - strange:
Blocker for the top (entry cap) complete with bottom (underside) holding bracket and entry (gauge tube):
and for the bottom (petrol tap):
Let the testing commence:
Result: Failed miserably - back to the workbench ! Although to be fair the air leaks where from sections of the tank that were not touched and where you would least expect them (top of the tank in good undamaged areas), the underside appears to be sealed up nicely - strange:
SilkySmooth750
What does "Personal Text" mean?
I also really like the tank and how it sits. I like your determination and it really paid off. Going to make this bike stand out from the others.
