Home made guide and bashie

[Traumaboy]

Hey guys,
some of you may remember previous posts from me about bashies and guides for my dat project well its almost finnished i just have to make a top guide bit for it but here are some pics of most of the project.

The guide has spring tensioning to compensate (sp) for chain growth and shrinkage as you shift between the 3 chainrings.
The bash guard has rods across to stop objects from hitting the chain ring. but allows dirt to fall out. Probly the most solid bashie it mounts around the bb with iscg mounts.The whole thing is made from aluminuim. The roller that is on there is tempory because im making a roller with wider grooves.
Could you all please say what you think about it with pro's and con's because i need it evaluated for my project folio.
thanks
Craig.

 

[that_stoney_one]

looks pretty good! whats the weight on it compared to an e-13 or something alike?

 

[3viltoast3r]

Very interesting, looking like a success is iminent. How does the chainroller follow the chainline/front derailler. Also do you know how much it weighs compared to an e13 LG1 or something of similar?

 

[mountain_bike man]

looks awesome, tad chunky, but its really cool

 

[Sean]

I second the above post in asking for weight. Thing looks brutal! Did you weigh it before installation? I'd hate to be a rock smashing into it.

 

[Traumaboy]

Havn't weighed it yet but i guess i can do it tomorrow and i'll get back to you. i havn't put the cut outs in it yet because i wouldn't probly finnish it in time for handing it in for marking because i broke my thumb.itis heavier than i wanted because i couldn't get the aluminium i wanted so i had to get 6mm aluminuim instead of 5mm or 4mm.

 

[Mammy]

First of all, good onya for getting hands-on and having a go.
That spring-loaded roller seems like a good idea but with a properly dialled-in derailleur, is there really a need for it? Either way, it's a cool thought.
EDIT: Just realised it's for the front shift. I take that back, it's a top idea.

As for the bash guard itself, how much chainring clearance are you taking away with that unit? The bike's clearance seems to be compromised a fair bit. Maybe streamline it a little?
Also, because there isn't a smooth 'undertray' for the chain-ring, I wonder whether those ridges from the rods could snag up the bike on some ragged terrain?
As I said before, thumbs up for effort and initiative.

 

[benny the kid]

geez that looks beastly
i like the spring on the roller too
ill pay you to make me one!!!

 

[Jon]

Matey,good effort. I made my guide out of 10mm lexan, sort of like a Truvativ box guide. Only a single ring on the front though.
A second version may be to remove the outside cover nearest the big ring and trim back the inner shield. Then get a strip of ally plate rolled up to follow the outside of the big ring. Weld it to the inner shield and presto, another 30mm clearance. Would like pimp if you drilled the narrow strip before welding it on too.
Good luck, make sure you post the finished article.

 

[Tazed]

Chunky - plan on shedding wheels mid-flight and landing on it? Looks tough enough!

 

[AngoXC]

Looks fair beasty to me man, good work!

In terms of the bottom roller, I personally think it protrudes a little far to be practical. If your pumping it hard and it slips off, or jams, there is a distinct possiblity it may snap off. maybe moove it closer to the actual guide.

Another option is to make say a 'steped' (cant come up with a better description sorry) roller, similar to that of many other dual ring/shift guides. The 'steps' will allow for the changes in chain growth as you shift though the chain rings. placing one of this on the top part of the guide might also help retain it. (been 'modding' an older MRP guide myself and Im thinking this may be the way to go personally...)

Again, great work!

EDIT; just realised you more or less have to have the roller out that far, otherwise you get very little wrap on the smaller chain rings.

 

[whitey89]

Looks fairly solid, how well does that kind of aluminium stand up against rocks?
Loving the springed roller, have you taken it for a test ride yet?

 

[Tazed]

Y'kmow, a triple-bashy is actually a pretty good idea.
There's nothing out there that can cover a 44T triple, and plenty of us have take teeth off the big ring over rocks that were just that leeeeeetle bit to high.

Simplify the build and seriously consider how you could market it.
My only other comments would be to rotate the bashy about 15 degrees towards the rear (set stays).
There's a gap there that could hang the bike if you're going slowly.
I'd suggest a solid plate under the rings, too, with some grooves cut into it for mud removal. Right now, all those little bars joining the 2 pieces are asking to hook up if grounden over something.

 

[Traumaboy]

It works all right down stairs and stuff but i havn't givin it a real go up bush yet still waiting for the doctors to decide wether my thumb is broken or not. When i was doing the testing of the aluminium it stands up to huge impacts like i got my test peices some H.D.P.E and mild steel, Al etc and put it the vice and belted it with a sledge hammer the Al didn't realy bend got a scratch and a slight warp but thats it. The reason why i made the bashie was cos i was sick of bending chain rings and grinding teeth of my cogs. About a week before i mounted the bashie i stacked it and bent my chain ring when my bike fliped in to a tree. My chain ring is is bent that it wants to pick up the chain from the 2nd cog . You maybe thinking why the spring well not only does it alow for chain growth it dampens the chain wip.

i should have a weight for it this arvo.

 

[Nathan_]

Congrats on the initiative to get your hands dirty and a better understanding of your bike

Weight + clearance would be my only concern

 

[Traumaboy]

clearance was an issue with the guard but when i looked at it. i still scrap on the chain ring normaly so i though its better to scrap on the guard and not my chain ring.

 

[whitey89]

clearance was an issue with the guard but when i looked at it. i still scrap on the chain ring normaly so i though its better to scrap on the guard and not my chain ring.

True, i guess a pro in this regard it that the roller is higher than the bashy. I hate it when the roller hangs down and gets destroyed on rocks.

 

[wombat]

For the purpose of your report and analysis, weight and clearance are obvious issues, maybe mention something about the complexity of assembly? Ideally it might be nicer to have something that goes together with a few less bolts for ease of servicing and cleaning etc.

But all that aside, congratulations!
That is a new take on the concept, and it's fucking cool. Major kudos for working through the project and coming out with something innovative and usable.

Now pull it off the bike and take some nice photos before you go and bash the shit out of it!

 

[Traumaboy]

Hey guys
i weighed the bash guard part and it comes in at around 350g and that without the cut outs that im putting in it tomorrow ill weigh the rest tomorrow at school in my free and in DAT.

 

[Reubs]

I've made a few chainguides myself in the past but they were all basically copies of other designs with some tweeks. That is a brand new train of thought in my opinion and some damn good ideas as others have said. Kudos to you!

A problem i can forsee is the possibility of jamming up the chain inside the device. How easy is it to drop off the bottom cage on the trail? to be able to remove it with an allen key is a definate bonus. it looks like this is how you possibly have it set up but that leads to my next point.

Are all those bolts necessary? i would guess that you could probably remove half of them and still retain the strength you want. That would help get the weight down since they are steel bolts.

I would add a skid plate to the bottom to help slide over rocks/ logs/ bridges. 1mm alloy would be good.

Chain tensioner looks well executed. good job! just need to make sure the spring tension isnt too high or it can effect your rear shifting (learnt this years ago with a bullet bros tensioner- google it...)

let us know what marks you get!