Register FAQ Community Calendar Today's Posts Search
Go Back   ScootDawg Forums > Performance :: Maintenance :: Technical > 125cc - 249cc
Reply
 
Thread Tools Search this Thread Display Modes
Old 10-10-2018, 05:48 PM   #1
soberinphoenix77   soberinphoenix77 is offline
 
Join Date: Sep 2018
Posts: 23
No exhaust

Exhaust fell of. Runs better but worried about damage. Gets great air flow and running better. Should I worry

Sent from my A574BL using Tapatalk



Login or Register to Remove Ads
  Reply With Quote
Old 10-11-2018, 12:14 PM   #2
Gene563   Gene563 is offline
 
Gene563's Avatar
 
Join Date: May 2015
Location: Lanoka Harbor, NJ
Posts: 63
Where did it break.? I wouldn't run it (for long) if it was open from the cylinder head, but a missing muffler would be ok for a short time. With a straight pipe, I wouldn't be sure about damage, but it would be loud.
I had an over rich problem that ultimately clogged my stock muffler (catalyst). It gave me running issues after tuning the carb. I pulled the muffler and it ran great. I ended up getting a performance muffler.
  Reply With Quote
Old 10-11-2018, 12:17 PM   #3
soberinphoenix77   soberinphoenix77 is offline
 
Join Date: Sep 2018
Posts: 23
The studs broke at the Port how do I get them out to replace them. I need this to keep running as its my only transport.

Sent from my A574BL using Tapatalk



Login or Register to Remove Ads
  Reply With Quote
Old 10-12-2018, 01:40 PM   #4
Gene563   Gene563 is offline
 
Gene563's Avatar
 
Join Date: May 2015
Location: Lanoka Harbor, NJ
Posts: 63
That sucks. You'd have to drill them and use and easy out, or similar, to back them out. Perhaps there's a machine shop close by that could remove them for you.
The replacement studs are cheap.

P.S. If there is any of the stud sticking out from the head, you could try Visegrips to remove it.
  Reply With Quote
Old 10-13-2018, 10:51 PM   #5
neo71665   neo71665 is offline
 
Join Date: Sep 2018
Location: arkansas
Posts: 38
No exhaust that close to the head will burn the valves if ran for any period of time.



Login or Register to Remove Ads
  Reply With Quote
Old 10-17-2018, 08:42 AM   #6
soberinphoenix77   soberinphoenix77 is offline
 
Join Date: Sep 2018
Posts: 23
Now I'm confused. No muffler or no pipe means same problem. No backflow. Why would one make a difference over the other? There is no difference between this and a car with a straight pipe. It's louder and runs better. I checked valves and lash. Why have I ridden this nearly 200 miles now and it still runs fine? I would like some real definitive answers. Please show me the science

Sent from my A574BL using Tapatalk
  Reply With Quote
Old 10-19-2018, 02:49 AM   #7
neo71665   neo71665 is offline
 
Join Date: Sep 2018
Location: arkansas
Posts: 38
Momentary flow reversals expose the valves to cold ambient air on the backside, or at least to high temperature differential. If that's the real failure mechanism, even a short exhaust is sufficient to prevent this. That cold back flow creates a lean condition when the cam overlaps cold air enters the cylinder. Lean equals hot. With that even short pipe if anything gets sucked back in it is hot exhaust gas and not cold fresh air.

Will it happen overnight, no but at 200 miles I bet the damage has started happening.

Believe what you want but I've personally burnt a valve in a chevy v8 with quality race parts (my drag truck) running it with no headers. The Chinese metallurgy these parts are made of are questionable at best.
  Reply With Quote
Old 10-19-2018, 06:55 AM   #8
soberinphoenix77   soberinphoenix77 is offline
 
Join Date: Sep 2018
Posts: 23
[emoji23] that's what I want to hear.. I'm not really worried about valves. I can fix that. I just need to be able to work a few more days and I will put her up and call it a season

Sent from my A574BL using Tapatalk
  Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 07:47 PM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.