Finally got the Mack Mag built!

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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.
View attachment 82274
Man Furry you’re always on point on these forums! Kudos to you! That’s a great idea thank you! I did however rearrange my handlebar situation and cut the stock throttle grip down a bit which allowed me to sleeve the bikes actual grip back over it, for now everything seems to be working out well!
7A93F052-2722-4058-B317-5D20EB66805F.jpeg
 
Man Furry you’re always on point on these forums! Kudos to you! That’s a great idea thank you! I did however rearrange my handlebar situation and cut the stock throttle grip down a bit which allowed me to sleeve the bikes actual grip back over it, for now everything seems to be working out well!View attachment 82279
Hey it was Crassius' idea not mine!
I still think you should switch the shifters to the opposite side but meh, whatever makes you happy, you know. :)


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!
My guess, and it is just a guess, is that the fuel is foaming inside the carb bowl because it is not rigidly attached yet. If it has any wiggle room it can shake like one of those paint mixer things. That's why I was saying about putting something between the carb and the frame so they can be strapped snugly together with a cable tie. The foamed fuel would cause a lean a/f ratio, consistent with the symptoms you describe.
 
Hey it was Crassius' idea not mine!
I still think you should switch the shifters to the opposite side but meh, whatever makes you happy, you know. :)



My guess, and it is just a guess, is that the fuel is foaming inside the carb bowl because it is not rigidly attached yet. If it has any wiggle room it can shake like one of those paint mixer things. That's why I was saying about putting something between the carb and the frame so they can be strapped snugly together with a cable tie. The foamed fuel would cause a lean a/f ratio, consistent with the symptoms you describe.
But wouldn’t leaner show on the plug? When I pull my plug now it’s dark and oily doesn’t look lean... but I do need to do why you described and attach the carb to the frame more solidly.
 
But wouldn’t leaner show on the plug? When I pull my plug now it’s dark and oily doesn’t look lean... but I do need to do why you described and attach the carb to the frame more solidly.
I think it wouldn't show on the plug because the rich condition returns when you slow down or idle the engine at a standstill so the plug would get a fresh coating of oil. We'll see what happens anyway.
 
I think it wouldn't show on the plug because the rich condition returns when you slow down or idle the engine at a standstill so the plug would get a fresh coating of oil. We'll see what happens anyway.
Hmmm I definitely don’t want to run lean. Sounds like it’s four stroking at WOT but maybe your right about the plug re-oiling itself at idle. Worries me a little bit, I’ll try and temporarily rig something between the carb and frame and see if that changes anything.
 
I am interested in your cylinder head! How is it working/ cost? Also does it produce more RPM? Also what is it called?? Carcher
 
I am interested in your cylinder head! How is it working/ cost? Also does it produce more RPM? Also what is it called?? Carcher
It was about $45 and it works great... it’s a higher compression head and it produces more power.
 
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.
View attachment 82274
Here’s another idea I really like for getting unwanted shifters and accessories off the main bar.... $15
9BF761EA-B022-462F-946B-F9C6803E4C0A.png
ED6FA665-99E1-4168-AE5D-33527D4ABED0.png
DEB4E1B8-5193-460F-A4CC-80B5A88C4172.png
 
Here’s another idea I really like for getting unwanted shifters and accessories off the main bar.... $15
View attachment 82282View attachment 82283View attachment 82284
I just fitted one of these, but I have plenty of room for (from left to right) rear gripshifter, front rapid-fire shifter, rear brake lever, clutch lever, tach, (extension bar mounts), small light, speedo, bell, front brake lever, and twist throttle all on my new narrower (610mm) handlebar.
The phone, I believe, is better on the top tube of the frame because there's slightly less shocks from the road surface in between the axles.
I am using the extension bar just as a support/mount for the Bluetooth stereo speaker. :D
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Alrighty I’m at a loss at the moment. I re-jetted my NT carb all the way down to 60 and it’s still 4 stroking at WOT. I then switched over to a new dellorto clone carb, which is really nice as far as throttle response and low-mid range, and also jetted it down to 60 and STILL 4 STROKING!!!?? I’m so confused, I’ve tried 3 different plug types and they all come out black and oily after running WOT and pulling the plug for a check. What is going on here? I have since secured the carb to the bike and I know it’s not running lean that’s for sure... what can be my issue I’m about to go crazy!?
 
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