0 Members and 1 Guest are viewing this topic.

*

Offline NMKawierider

Just something you don't hear of everyday
« on: September 08, 2015, 04:29:36 pm »
The other day when I was testing the new clutch setup the last thing I did was take it to some straight roads so I could test the top end. By the way it still got 62mph. Anyway, after the last run I noticed the engine running different and what sounded like an exhaust leak. I assumed I had blown an exhaust gasket somewhere.

So last night I decided to find it- so I started it and put my hand over the exhaust outlet and sure enough it wouldn't build pressure at all and I could hear a bad leak. With one hand covering the exhaust discharge I used the other to see if I could feel where it was coming from. It was one of the two spring-loaded pressure couplings and it was from the bottom side. I grabbed the pipe and muffler and gave it a little twisting action and it popped back in place and sealed well. No more leaks. Thought the muffler bolts were loose so checked them. They were tight...springs all good..head piped all tight. So the only other thing I can think of that could cause them to push apart is pressure from within. I was up there pretty high in the RPMs to get that 62mph so the question has to be...how much back pressure does it take to overcome the forces of those four springs. I'm sure it's pounds..not ounces ...and that can't be good.  You guys with the aftermarket mufflers will probably never encounter this situation. I'm going to make a few "adjustments" to the muffler to help it flow a bit better but looks like an aftermarket unit is in my future.

Just thought I would share.
2015 Z Force 800 (53") EPS -
Custom Air Intakes | Custom Exhaust Mod | SuperATV Harness | Custom Fenders | Custom Skid/Rock Sliders | 27" GBC Grim Reapers | Seizmik Mirrors |Конструктор (Rodin's) Doors | Dr Pulley Sliders | 1.5" Wheel Spacers | BENZ Silencer (as needed) | SATV Flip Windshield W\ Rear Shield | Dual Light Bars | Diamond Plate Storage | Magellan TRX7 GPS| Bandit Springs

My Videos On YouTube

*

emersonsc

Re: Just something you don't hear of everyday
« Reply #1 on: September 09, 2015, 10:48:47 am »
The other day when I was testing the new clutch setup the last thing I did was take it to some straight roads so I could test the top end. By the way it still got 62mph. Anyway, after the last run I noticed the engine running different and what sounded like an exhaust leak. I assumed I had blown an exhaust gasket somewhere.

So last night I decided to find it- so I started it and put my hand over the exhaust outlet and sure enough it wouldn't build pressure at all and I could hear a bad leak. With one hand covering the exhaust discharge I used the other to see if I could feel where it was coming from. It was one of the two spring-loaded pressure couplings and it was from the bottom side. I grabbed the pipe and muffler and gave it a little twisting action and it popped back in place and sealed well. No more leaks. Thought the muffler bolts were loose so checked them. They were tight...springs all good..head piped all tight. So the only other thing I can think of that could cause them to push apart is pressure from within. I was up there pretty high in the RPMs to get that 62mph so the question has to be...how much back pressure does it take to overcome the forces of those four springs. I'm sure it's pounds..not ounces ...and that can't be good.  You guys with the aftermarket mufflers will probably never encounter this situation. I'm going to make a few "adjustments" to the muffler to help it flow a bit better but looks like an aftermarket unit is in my future.

Just thought I would share.

Every ZForce 800 i've sold so far, EX or not, has had an issue where they start to leak where the muffler connects to the head pipe section. I have yet to find what is causing it. I believe the springs are getting weak due to heat. I also think the exhaust doughnuts they use are too small and dont form a tight enough seal.

*

Offline NMKawierider

Re: Just something you don't hear of everyday
« Reply #2 on: September 09, 2015, 03:01:33 pm »
The other day when I was testing the new clutch setup the last thing I did was take it to some straight roads so I could test the top end. By the way it still got 62mph. Anyway, after the last run I noticed the engine running different and what sounded like an exhaust leak. I assumed I had blown an exhaust gasket somewhere.

So last night I decided to find it- so I started it and put my hand over the exhaust outlet and sure enough it wouldn't build pressure at all and I could hear a bad leak. With one hand covering the exhaust discharge I used the other to see if I could feel where it was coming from. It was one of the two spring-loaded pressure couplings and it was from the bottom side. I grabbed the pipe and muffler and gave it a little twisting action and it popped back in place and sealed well. No more leaks. Thought the muffler bolts were loose so checked them. They were tight...springs all good..head piped all tight. So the only other thing I can think of that could cause them to push apart is pressure from within. I was up there pretty high in the RPMs to get that 62mph so the question has to be...how much back pressure does it take to overcome the forces of those four springs. I'm sure it's pounds..not ounces ...and that can't be good.  You guys with the aftermarket mufflers will probably never encounter this situation. I'm going to make a few "adjustments" to the muffler to help it flow a bit better but looks like an aftermarket unit is in my future.

Just thought I would share.

Every ZForce 800 i've sold so far, EX or not, has had an issue where they start to leak where the muffler connects to the head pipe section. I have yet to find what is causing it. I believe the springs are getting weak due to heat. I also think the exhaust doughnuts they use are too small and dont form a tight enough seal.

I was out again today and tached it up only to about 6500 on a few situations and the other one (upper) became un-set..meaning it was not in the socket correctly. That one I had to loosen the muffler and wiggle it to reset it. It did seal though and I re-tightened the muffler. I only have 300 miles on this but you might have something on the heat and springs. When I noticed it I grabbed leather work glove from the box to do some wiggling and when I touched it to the discharge pipe, it burned right through it...like it was red hot. That means it may be even hotter back by the springs.
2015 Z Force 800 (53") EPS -
Custom Air Intakes | Custom Exhaust Mod | SuperATV Harness | Custom Fenders | Custom Skid/Rock Sliders | 27" GBC Grim Reapers | Seizmik Mirrors |Конструктор (Rodin's) Doors | Dr Pulley Sliders | 1.5" Wheel Spacers | BENZ Silencer (as needed) | SATV Flip Windshield W\ Rear Shield | Dual Light Bars | Diamond Plate Storage | Magellan TRX7 GPS| Bandit Springs

My Videos On YouTube

*

Offline NMKawierider

Re: Just something you don't hear of everyday
« Reply #3 on: September 09, 2015, 05:49:14 pm »
Well, after taking a look I did find one issue. The parts list shows all the exhaust springs to be the same, and the springs on the lower Y coming from the rear cylinder are very well stretched..20% of their 76mm length as recommended, however, the upper four, going into the muffler itself are hardly stretched at all...in fact I removed them with a pair of plyers. There is 77 mm between the two hangers and the spring is 76mm so they are stretched a whapping 1mm. That connection isn't tight enough so I just ordered two sets of Moose Racing 63mm exhaust springs at 13.95 per set for that joint. That will fix that connection.  What next?..
« Last Edit: September 10, 2015, 06:54:26 pm by NMKawierider »
2015 Z Force 800 (53") EPS -
Custom Air Intakes | Custom Exhaust Mod | SuperATV Harness | Custom Fenders | Custom Skid/Rock Sliders | 27" GBC Grim Reapers | Seizmik Mirrors |Конструктор (Rodin's) Doors | Dr Pulley Sliders | 1.5" Wheel Spacers | BENZ Silencer (as needed) | SATV Flip Windshield W\ Rear Shield | Dual Light Bars | Diamond Plate Storage | Magellan TRX7 GPS| Bandit Springs

My Videos On YouTube