Finally got the Mack Mag built!
- Thread starter Kpi890
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FurryOnTheInside
In Memoriam
Looks like it's coming along nicely. I like the idea of the self fusing tape. I have a lot of sticky residue from the electrical insulation tape on my bike lol. 
Carb: when you tie one cylinder/ convex shape against another it tends to wiggle and rock, so you might make something to fit between the two which will stop that. It could be hot melt glue pumped straight into the space while the carb is in position, or it could be epoxy putty or even liquid epoxy held in shape by some electrical insulation tape.
Handlebars: I think it was @crassius who posted a photo recently in the thread about gears on a mountain bike build of a stub thing that fits to the bars and can be used to mount a gripshifter at right angles to the bar. I would probably try a SRAM trigger shifter, where the up and down levers are both operated by the thumb (as opposed to the Shimano ones that are thumbnail and index finger).
You could also try just putting the gripshifter inboard of the brake, for now.
Edit: bloody autocorrect never lets me spell Shimano. Or autocorrect.
Carb: when you tie one cylinder/ convex shape against another it tends to wiggle and rock, so you might make something to fit between the two which will stop that. It could be hot melt glue pumped straight into the space while the carb is in position, or it could be epoxy putty or even liquid epoxy held in shape by some electrical insulation tape.
Handlebars: I think it was @crassius who posted a photo recently in the thread about gears on a mountain bike build of a stub thing that fits to the bars and can be used to mount a gripshifter at right angles to the bar. I would probably try a SRAM trigger shifter, where the up and down levers are both operated by the thumb (as opposed to the Shimano ones that are thumbnail and index finger).
You could also try just putting the gripshifter inboard of the brake, for now.
Edit: bloody autocorrect never lets me spell Shimano. Or autocorrect.
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Good idea on the handlebars! I’ll check into those options! And as far the carb suggestion are you talking about gluing the intake to the seatpost? Also while I’ve got you I figured I would ask. As I add higher performance parts do I want to be jetting higher or lower? Say if I add an MZ 65 pipe will I want to jet higher(richer) into the 70’s or lower(leaner) into the 60’s, assuming the stock jet in the NT is a size 70?Looks like it's coming along nicely. I like the idea of the self fusing tape. I have a lot of sticky residue from the electrical insulation tape on my bike lol.
Carb: when you tie one cylinder/ convex shape against another it tends to wiggle and rock, so you might make something to fit between the two which will stop that. It could be hot melt glue pumped straight into the space while the carb is in position, or it could be epoxy putty or even liquid epoxy held in shape by some electrical insulation tape.
Handlebars: I think it was @crassius who posted a photo recently in the thread about gears on a mountain bike build of a stub thing that fits to the bars and can be used to mount a gripshifter at right angles to the bar. I would probably try a SRAM trigger shifter, where the up and down levers are both operated by the thumb (as opposed to the Shipman of ones that are thumbnail and index finger).
You could also try just putting the gripshifter inboard of the brake, for now.
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FurryOnTheInside
In Memoriam
No I don't mean to glue it on, the hot melt glue would have a very low adhesion to the cold, smooth powder coated frame and the metal of the carb, but it would mould into the shape of the space between the two convex surfaces, so when you use the cable tie to secure the carb there will be no rocking and wobbling. I have a plastic adapter for my plastic air filter so I was able to use a knife to make the appropriate shape to fit against my seat tube, but I did use hot melt glue for steadying a few other bits including the tachometer.
High performance is just a marketing term, utterly meaningless lol, but I believe @gary55 mentioned that the tuned pipe has a leaning effect so you would need a larger jet, assuming the stock jet is correct. But the stock jet is probably a bit larger than it needs to be with the stock exhaust (and that's good for the break-in stage), so you never really know until you try it.
Also for the gear shifters, I find that I like having the rear gripshifter on the left, because I don't want to have to let go of the throttle at all, and I am twisting the throttle back with my right hand to go faster, so it should be natural to twist the left hand gripshifter the same direction to stay in the correct gear.
I actually ended up putting a gripshifter (inverted) on the left side for the rear gears and also a thumb shifter for the front gears on the same side. So at the very least I would say switch your shifters around and have rear gears on the left, inverted.
If you decide to try the sawn off bar end, be aware that of the few bar ends that have a round cross section, most of them have a larger diameter than your handlebars, probably 25mm instead of the 22.2mm that you need to fit a gear shifter. Those that are 22.2mm are nearly all old stock/used early steel ones. When you see bar ends advertised as 22.2mm they are nearly always just referring to the handlebars that the bar end is made to clamp onto, not the diameter of the grip section of the bar ends themselves.
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Tyler6357
Well-Known Member
Sweet ride!! I particularly like the mag wheels
Do you by chance have a picture of what you’re talking about?
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bike4life2
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I am bike4life, just at school and forgot login credentials as they are auto-saved at home.
Why did you remove the rear disc brakes ? I have a similar mongoose bike w/ disc brakes and you just have to extend the disc brake over 1/2" with some steel plate and then extend the actual wheel over 1/2" with 4 washers stacked.
Why did you remove the rear disc brakes ? I have a similar mongoose bike w/ disc brakes and you just have to extend the disc brake over 1/2" with some steel plate and then extend the actual wheel over 1/2" with 4 washers stacked.
FurryOnTheInside
In Memoriam
He means mountain bike bar ends. I guess they were first popular with cross country mountain bikers, uphill cyclists did wear spandex before the invention of lycra but then it is useful stuff if you don't want to chafe to death lol.
Crassius posted these photos:
https://motoredbikes.com/threads/can-you-still-use-your-shifters.52886/#post-463742
Here's my picture of some mtb bar ends, including a pair of rather rarer alloy 22.2mm bar ends. This narrow diameter is usually (not always) steel, and old, since the larger diameter is much more comfortable.
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Thanks for the replies! The bike is running great so far took it out on the maiden voyage today! First bike I’ve built with absolutely zero vibration at all RPM ranges. I’m still with the stock jet, which feels rich and four strokes, and did have to move the c clip to the highest notch since it was running really rich. That brings me to my question... at idle with the clutch pulled I can rev the bike and it’ll rev up and return to idle normally just like before, however while I’m riding if I pull the clutch to coast or whatever the bike takes longer than normal to returun to idle... what is causing this? The rpms seem to hang for a bit and then eventually return to the idle rpm... does this have to do with the extended intake by chance? This engine was actually broken in on another bike and the carb was placed normally on the intake manifold so this is my first experience with an extended intake. Just curious if anyone knew what might cause this? Thanks!
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