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The frame is turning out to be a little wider than I'd planned. I discovered the extra width was needed for chainline clearance. I don't think it will be too bad on the legs coz you will be sitting up a little higher than the top tubes with your legs out in front, we'll see. I also have a wider bb from a Stingray clone I could use if the chainline needs to move outward. In the past my builds have sacrificed style for function, less so on this build. I've also put a lot of rake on the headtube hoping to counteract some of the negative trail, I don't want to put all this time/money into a build that's no fun to ride, it's all kind of an experiment at this stage. I'm not into 'trailer queens' but wanted to push the envelope on this one. Never thought about a lock out, if the lines don't leak I shouldn't need one or have you found differently?
 
i don't think your lines are going to leak because they are all going to be threaded into your ports right? but I can tell you that you may have problems with the cylinder leaking. mine is starting to leak a little from wear and tear. i will have to replace it soon. I made mine just for show. i now have a lock on the frame and I can ride all day without any air. how high is your bottom frame from the ground going to be when in riding mode?
 
Max ride height will be as you see (width of a 2x4). My plan has been to cruise near full height as I imagine without dampning the ride will be bouncy anyway. I never thought about the cylinder leaking down with wear. Did you buy yours new? If so I'm surprised it deteriorated so quickly, perhaps a side effect of running full pressure into the system. That's why I bought an adjustable reg for my bottle, thinking it may extend the system's life span. What'd you use for a lockout? Perhaps a piece of tubing with a slot cut the full length? Time will tell how reliable the whole system is, it's all an experiment anyway. At worst I can use all the parts to make something else if it doesn't work out. :roll:
 
Needed to build a jackshaft so I thought I'd share how I did it. Started with a nice old chrome hub, removed the cassette and using my grinder cut the lockring and removed the stack of gears. I decided to use the 18 tooth ring along side a 16 tooth freewheel (chrome of coz).
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After carefully lining things up, clamped it with visegrips and using a caliper, rechecked the depth from the teeth to the hub flange. I masked the freewheel thread with several layers of tape to protect from potential welding spatter. Aim the mig directly down into the gap and away from the freewheel thread.
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About a dozen good spot weld later everything seems solid. Remember to weld a couple, quench with wet rag and repeat until done. Didn't even damage the chrome on the other side.
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Finished product waiting for other things to be completed
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OCD said:
Max ride height will be as you see (width of a 2x4). My plan has been to cruise near full height as I imagine without dampning the ride will be bouncy anyway. I never thought about the cylinder leaking down with wear. Did you buy yours new? If so I'm surprised it deteriorated so quickly, perhaps a side effect of running full pressure into the system. That's why I bought an adjustable reg for my bottle, thinking it may extend the system's life span. What'd you use for a lockout? Perhaps a piece of tubing with a slot cut the full length? Time will tell how reliable the whole system is, it's all an experiment anyway. At worst I can use all the parts to make something else if it doesn't work out. :roll:

i bought it brand new. its a very small pin hole leak. it does take a large amount of pressure to hold your entire weight plus the weight of the bike. i also found out that you need more pressure so that it does not bounce when riding over bumps. i used a shock from a car as my lock.

do you have all of your parts for your tank?
 
I have an adjustable regulator (100-1000psi) and plan to get a 4500psi air/N2 tank. I hope to wait until the bike is a roller before I go down to the local paintball supplier to try different sized tanks. Even if I get a deal off eBay later, at least I'll know what size/shape to look for. As mtb airshocks usually need about 150-200psi I thought I'd be safe but time will tell. Perhaps as yours has no linkage things are different, in fact I'm sure there are many, many variables and we'll only learn through experimenting. I'm hoping to get the bottom of the frame together tomorrow, we'll see what happens. Did you replace your air cyl with the shock or just wedge it in somehow?
 
took the metal rod out of the shock and placed it where the air cyl. goes. works like a charm. would like to make my own fork before painting it. i just have it sitting in the garage for now. whats the next step for your build?
 
Today's plan is to get the bottom of the frame tacked together, then finalize where the bottom bracket will sit so I can measure back to find where the seat will be. Once I know the seat position I can make the mounts for the rear suspension, once that's done I'll have a rolling chassis. I'd like have this all done by the weekend. It's finally warming up where I am, supposed to be 30c (90F) most of week, hopefully that won't affect my motivation.
 
Today's effort: The bike is now officially free standing. Need to make the lower suspension, jackshaft and seat mount next. 8)

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Completed the lower suspension mount, I'm planning to connect them together for additional strength. Started on the seat mount as well.

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the two bars on top. are those for your seat?

Yes, will have two more bars curve up from the main frame for support. A seat pan will then bolt on top. Will also add a curved section to tie the two suspension mounts together.
 
Tacked in the last two seat supports, suspension mount brace and built a mock-up seat. I slightly underestimated how far forward the tire moves forward during drop...gonna be tight.

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looking good. how high is it from the bottom tube to the ground when lifted? i like how the seat does not go above the tire when in the up posistion. i wanted to do that to mine, but it did not work out for me. what gauge tubing are you using?
 
The ground clearance of the bike is the width of a 2x4 (3.75") at ride height, which is about the same as a stock bike's pedals. If you take your time you can get a lot done with basic tools, I'm not exactly employing a high tech jig; complete wheels clamped between 2x4s for wheel base alignment and various spirit levels for vertical measurements. I'm trying 3/4" EMT for this build as an experiment, the zinc coating removed at all welding sites of course. The downtube is 1 1/4" .065 (I think) it's quite light so far, at least compared to my last build which weighs in at 65 lbs. I like the current seating position but as previously mentioned, I have a couple inched less leeway for saddle placement than I originally calculated due to the horizontal movement of the rear suspension. The bike is so low I can't believe it, while working around the shop you're somewhat in danger of tripping over it, I don't exagerate when I say the handle bars hardly come above my knees. Got one jackshaft drop-out done tonight, hopefully the other tomorrow.
 
Okay, will do. I'll have to drag my wife out to the shop. I suppose realistically the handlebars come to about mid-thigh level but compared to my downhill mtb which comes to upper abdomen height, it's way low. :mrgreen:
 
Jackshaft mount is tacked in, chainline clearance is tight with the tire, but I think it will be okay. Rear air cylinder mount is done, it's almost ready to stay up without a block of wood under it. :wink:

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Had a productive evening tonight, got a start on the rear chain tensioner. Began with an old school mtb one by cutting away anything unnecessary. Fabricated my own mount and cut a strut from sheet aluminum, seems to have a clear chainline.

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Made my own idler pulley too by using skateboard bearings and 3 circles of this plastic sheet that was left in my workshop by the previous owner.

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