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Smokey
01-28-2015, 10:41 PM
Hi,


I have started a Tomahawk project, and thought I should share some of my progress. So far it has gone pretty well except for my terrible welding skills. I am definitely going to need to use filler to make some of the welds look better.


http://s21.postimg.org/z2cfrx0uv/IMG_0274.jpg


I have been taking a few pictures along the way and blogging them here:


http://laycycle.com

I like the domain name I managed to find. :stooge_curly: The blog is a bit behind but I will be updating it over the next week.

I have the bike almost ridable, but am struggling a bit working out what to do about braking. At this stage all I have tried is a simple old school caliper on the front wheel, but that has not worked..... Not even close to enough stopping power, I can push the bike along with brakes applied.

Neither my front nor rear hubs can accept disk brakes. Next I am thinking about using some v brakes, but I am not sure how much better than caliper brakes they will be?

Cheers

darnthedog
01-29-2015, 12:04 AM
Thanks for sharing your adventures.
V-Brakes and Calipers use 2 different levers. I am unsure exactly which one is which but it sounds like you may have V-brake handles pulling on Calipers. Swapping to caliper levers may give you better stopping power. No promises- but I have read that that can effect braking as one needs a longer pull to grip than the other.

As to switching to a disc brakes- there are multiple methods of doing that. There is a disc brake adapter that screws to a freewheel thread for example to create a mount for the disc for example. And there are multiple examples of building a mount that clamps to the spokes. That was developed by Peter_T in Australia. I forget who did a tutorial posting but if you can't find it I can research it for you. Just getting late for me at the moment.

Its looking pretty good though. Thanks for Sharing. Hope you get the brakes figured out.

Twinkle
01-29-2015, 06:04 AM
Hi There and welcome to the fun ( noticed first post )

The brake lever problem has reared its ugly head more than once or twice . vee brake levers are usually shorter and wont give enough leverage with old school caliper brakes
( see my electric shopper post ) we reengineered some vee brake mounts using the bridge from scrap MTB front forks , now the shopper both shops and stops

Ken uses the shopper as a comute to work bike and has found the new brakes work well .
hope this might help you
http://s29.postimg.org/yo8zplxjb/front01.jpg (http://postimg.org/image/wjomoivwj/full/)

http://s29.postimg.org/kf9d7jj0n/front02.jpg (http://postimg.org/image/7nv71198j/full/)


capture (http://postimage.org/app.php)

it has helped the 20mph shopper

regards emma

Smokey
01-30-2015, 01:03 AM
Thanks darnthedog and Emma.

I did try some different brake levers and that did improve the performance, but only a bit. Since posting I put some v-brakes on my rear wheel and they worked well. I really like your idea of using the bridge from mountain bike forks. Thanks! I am definitely going to try that for my front wheel.

The weight distribution of this bike seems biased to the front, so I think it is important I have some decent front brakes.

Cheers

KiwiRider
01-30-2015, 06:14 PM
Hi Smokey

Thanks for sharing your website. Some great stuff there!

Cheers

Smokey
02-04-2015, 04:24 AM
So I have made a bit more progress. I have managed to add a V-Brake to my front forks using the process suggested by Emma. Works way better, but I have to work on my cable routing.

I managed to squish the bike into our Prado, by lying the front seat flat and folding down the rear seats. Man these bikes are LONG...... Had to take another car to put the family in.

http://s10.postimg.org/wjbux6rcp/016.jpg

The first ride of any length was going OK. Couple of issues that I need to correct. The main one being the chain pulleys.

http://s10.postimg.org/5zj9v1qt5/015.jpg

I made some home made ones out of Ikea Chopping boards, but the Bearing I used had way too small an internal diameter (8mm). When trying to start on the mildest of uphill slopes I bent the axles very easily.

I have ordered some 12mm internal diameter ones, and have purchased some 12mm HEX couplers and will weld them to the frame as I read somewhere else on the boards from emma. This should mean I can also get the pulleys closer to the frame which will reduce the leverage on the bolt.


The other issue with my pulleys is that they are too wide, and get in the way of my right leg when pedalling. I have some 3mm aluminium and plastic composite panels that I may try to replace the thick outside walls with.

I put up another article showing some of the build on my blog -> http://laycycle.com I am still behind, but am enjoying going back through my photos and putting them up.

Cheers

bambuko
02-04-2015, 10:31 AM
...I made some home made ones out of Ikea Chopping boards, but the Bearing I used had way too small an internal diameter (8mm). When trying to start on the mildest of uphill slopes I bent the axles very easily...
I have used 10mm stainless steel bolts on my bike and after many, many hundreds of miles - not the slightest sign of trouble or bending.

Twinkle
02-04-2015, 07:50 PM
I have used 10mm stainless steel bolts on my bike and after many, many hundreds of miles - not the slightest sign of trouble or bending.

I have used both 8mm and 10mm HT and stainless bolts without problems .

Glad to hear the front brake is better , Kens folder has this mod on both front and rear brakes now and he is pleased with the result .

regards emma

bambuko
02-05-2015, 06:21 AM
Don't forget Emma that forces exerted on the pulley shaft will be the function of the angle that the chain changes.
So you and I with relatively modest changes will be OK.
Smokey on the other hand is doing two almost 90 deg changes.
That's lot of strain (and incidentally, also a lot of losses in the system - this is very inefficient chainline).
I am a great believer in avoiding pulleys if possible - they just sap your energy for nothing (although I accept that in the design like Tomahawk it is impossible to avoid them)

Twinkle
02-05-2015, 06:34 AM
Don't forget Emma that forces exerted on the pulley shaft will be the function of the angle that the chain changes.
So you and I with relatively modest changes will be OK.
Smokey on the other hand is doing two almost 90 deg changes.
That's lot of strain (and incidentally, also a lot of losses in the system - this is very inefficient chainline).
I am a great believer in avoiding pulleys if possible - they just sap your energy for nothing (although I accept that in the design like Tomahawk it is impossible to avoid them)

Point taken and noted Mr B ;) . In this case an extra support on the outside of the pulleys might help :juggle2: and double as a chain guide to stop bouncing , but won't help the wasted energy in drive train but might reduce the wasted energy bending bolts :joker: ...:taz::taz::taz:

regards emma