PK 80cc engine kit stock muffler problem- coming apart

GoldenMotor.com

mhillz

New Member
Mar 1, 2010
9
0
0
NJ
hey i recently picked up a pk 80cc engine kit and installed it on my bike. i followed the instructions on how to break it in properly and it has about 60 miles on it. the other day when i was out riding, about 3 mins into my ride, my muffler became very hot and feel off right above were the muffler becomes fatter. I rode it back home with the piece of muffler missing (it actually sounded alot better and also was giving me more pick up) the reason for me writing this is to find out while i wait for the replacement muffler to be shipped to me, is it safe to ride it now? i searched the forums too find out more detials but havent been able to find much, please post back what you think cause im DYING to ride it but dont wanta ruin the motor lol. thanks
 

crobo

New Member
Mar 24, 2010
94
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0
boston ma
I'm not sure on safety of the engine, i wouldn't think it would hurt the engine, but I'm not 100% sure. also... i cant beleive you melted your muffler off.... lol
 

mhillz

New Member
Mar 1, 2010
9
0
0
NJ
haha yea, but i called the guy back at pirate and he said i was the third guy to call within the last week with the same problem. he said the he feels the black matte exhaust on the pk 80cc kits is alot less heat resistant that the chrome finish. he is sending me a new one, free, but instead of the matt black, he said pk offers a new polish black finish that apparently can handle the heat more, but either way im eventually gonna install the high performance kit that i got from sick bike parts, jus waiting on my dads buddy to weld it together for me. he feels that will provide a lil more stability than the rubber pieces the give you to hold it together
 

crobo

New Member
Mar 24, 2010
94
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0
boston ma
it will def be more stable but make sure that you dont weld EVERYTHING together, the lengths of those pipes is how you tune the exhaust. if you want it welded then make sure you have it tuned first.
 

Gareth

New Member
Dec 8, 2009
123
0
0
Floriduh
You definitely NEED to mount the mufflers on the PK kits with hangers. Other kits you can get away without, but the PK's will all break without the support. and make sure your support bracket actually supports it...if it is loose it isn't doing anything.
 

mhillz

New Member
Mar 1, 2010
9
0
0
NJ
thanks for the advice, ya i got the new muffler today, seems to be built a lil more sturdier. i rode around on it for a lil bit and then checked the muffler for over heating and it was not too hot. ill def look into some temporary muffler mounts at least until i put the sbp exhaust kit on
 

Venlaw

New Member
Apr 7, 2010
30
0
0
Canada
Yeah mine did the same thing just the other day. 150km (93mi) on it, rippin' along a smooth surface, and off it went. Was quite hot.

It's not the welds that cracked. It separated around the welds.
 

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BarelyAWake

New Member
Jul 21, 2009
7,194
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Maine
... im eventually gonna install the high performance kit that i got from sick bike parts, jus waiting on my dads buddy to weld it together for me. he feels that will provide a lil more stability than the rubber pieces the give you to hold it together
Often ppl say/think along similar lines when they first get the SBP sys, I did too - but I gotta say I had no problems at all with it or it's hi-temp silicone for well over 3000 miles. I would recommend mounting it to yer bike as recommended by SBP, get it tuned, then later if it proves a prob or w/e welding it as ya wants...

ofc having said that, I later used a stock headpipe to replace those bits on a different build - but only because it was a vintage build, Ima fashion slave, & I had figured out it's tuning lol
http://motorbicycling.com/f13/catalytic-converter-mufflers-15857.html#post166497
 

shearbf

New Member
May 8, 2009
77
0
0
Muskegon,MI USA
I'd say that if you hang it on there with no brace support to the frame,they will all break someday. Espically during breakin miles when vibration is more.
GOOD LUCK!
 

StealthJPL

New Member
Sep 10, 2011
4
0
0
San Diego, California
Hey guys,

I recently purchased and installed a RAW 80cc bike engine. I did everything the instructions told me to and th3e installation was a success. I was riding home last night from work and the muffler fell off. My compression increased and the engine ended up dieseling. After I pulled the plug, I had to choke it to shut it down. I inspected the problem and found out that the muffler was missing. The bolts that hold the muffler stripped and now I have no way of installing a new motor unless I re-tap the muffler on. I was wondering if that is safe though. I am not a mechanic but I am an engineer in the Navy. I know how to use taps and dies to make a new hole so I can make it stronger but I need to find the muffler first or buy a new one. I do not want to tap it though if it will ruin the engine so that is why I am here. Do you guys think it can be done, or should I order a new chamber?
 

riff44raff

New Member
Nov 4, 2010
50
0
0
staton ca
i have had the same problems and not only with exuset bolts all the stock bolts i replaced with better bolts you can get a kit or go to home depo and use alen heads but back to the exusast( I cant spell ) anyhow try a longer bolt first that has worked for me on a few things better grade allen head bolt say a quaoter inch longer and rember if you tighten too much it will strip and if it dont work your only out 50 cent then you can start thinking drilling or heilocoil incerts good luck
 

StealthJPL

New Member
Sep 10, 2011
4
0
0
San Diego, California
Thanks. I decided to reboar the holes and make them a little bigger using a 1/4-20 thread. That should strengthen it so when I get the new muffler it will not fall off this time. Do you know about the carburator. Mine seems to make the engine run to fast. Also it is leaking fuel everywhere. Do they have better carbs elsewhere.