Flywheel And Swingarm

[FoxBansheeRacing]

I am thinking about getting my swingarm shortened(if mrmatt still does it). I am just wondering whether I should have it shortened 1 or 2". I do not want it to be a wheelie monster, just better traction for mx. I am leaning towards just 1". What would you guys with shortened swingarms suggest.

 

My second question is about flywheels and advancing the timing. I would like to have a faster rev and a little bit more bottom end(wider powerband). I am not looking to get into the motor much more than I already have, so how hard is it to get the stator and flywheel off? Between advancing timing and lightening the flywheel what would be a better mod to do? I have also heard that advancing the timing will raise your compression???

[sredish]

The 2" shortened swingarm does like to come up in my opinion. I'm sure there are other who disagree. I'd imagine the -1" is pretty nice.

 

Advancing the timing shouldn't raise the compression because your not changing anything in the combustion chamber. However, it will be more compressed at ignition, but the compression of the cylinder won't be affected. Someone please correct me if I'm wrong. Advancing the timing is a good bang for the buck, although, I've yet to do it, I'm stupid and lazy I guess.

 

Lightening the flywheel is also a good mod, but I don't know much about it, other than letting it rev easier.

 

Scott

[locogato11283]

i believe boonman will lighten your flywheel for you. talk to him about it.

[BdBanshee]

My second question is about flywheels and advancing the timing. I would like to have a faster rev and a little bit more bottom end(wider powerband). I am not looking to get into the motor much more than I already have, so how hard is it to get the stator and flywheel off? Between advancing timing and lightening the flywheel what would be a better mod to do? I have also heard that advancing the timing will raise your compression???

 

To install/remove these parts you first have to remove the gear shift lever and footpeg on the left side. Then remove the plastic stator cover. Using an impact, remove the nut on the end of the crankshaft holding the flywheel on. Then thread your flywheel puller into the flywheel until it stops, this is a left hand thread (lefty tighty - righty loosy). Then thread the bolt into the flywheel puller until it contacts the crank, then using 2 wrenches tighten the puller bolt up until flywheel pops off. Sometimes it will get tight and then you can tap puller bolt with a hammer and it will pop loose. This is a pretty simple job. After the flywheel is removed you can see the stator/timing plate. There are 3 - 10mm bolts holding it to the case, loosen these and then unplug wiring from harness. When reinstalling just reverse directions. But before putting flywheel back on you will need to rotate crankshaft until flywheel key is on top. Then you slide flywheel on crank and line up with key. Make sure it is seated fully and then torque flywheel nut to 59 ft. pounds.

 

I can change a timing plate and flywheel in about 30 minutes.

 

Both these mods work great on the Banshee. When done at the same time you will notice a big difference. I have been doing these mods for people since 1989 and never had anyone go away disappointed, you will like the results!

[nater006]

To install/remove these parts you first have to remove the gear shift lever and footpeg on the left side.

If you want a slightly quicker way... remove the shifter lever, and the stator cover bolts, and simply rotate the cover up and out of the way -- it'll still be on the shifter shaft though, but will rotate out of way and leave you lots of room to work.

[broke]

I would just go to a -2. That's what I have on mine, with a ported RZ motor and rocket pipes. The motor has more than enough power to lift the wheels anytime I want, but it is controlable and predictable.

MrMatt did mine and I can say he does extremely nice work. I ride with a buddy that has a -1 and wants to change to a -2 if that tells you anything.

 

I did some pretty steep hill climbs last weekend and you just kind of change your ridind style. With the stocker I had to watch the front to make sure it didn't come up and at the same time weight the back for traction. Now I just kind of stay low and over the front and don't even think about weighting the back anymore.

 

Advancing the timing does not raise your compression, but can make a border line engine have to change to a slightly higher octane to keep detonation at bay. I'm sure one of the smarter people on here can tell you why.

 

Lightening the flywheel is a great mod with little or no side effects. Lets the motor rev quite a bit faster.

 

If I were you I would do them at the same time if finances permit. You're already in there, might as well.

 

 

 

 

Good luck

broke

[FoxBansheeRacing]

Will advancing the timing give me a broader powerband on the bottom end? I just dont understand why my power is so damn peaky, every mod I have done since I have had it has been to get more low end and wider powerband. I rode another banshee yesterday with just pipes and its power came on nice and smooth. The only thing that I can think of that would be causing the peaky power is the v-force reeds????

[Stinco]

can these mods be done to a stock banshee, (the flywheel/ timing) or is it more recommended for ones with heavy mods, pipes, reeds, etc??

Would there be a big difference in a stock shee??

thanx

[BdBanshee]

can these mods be done to a stock banshee, (the flywheel/ timing) or is it more recommended for ones with heavy mods, pipes, reeds, etc??

Would there be a big difference in a stock shee??

thanx

 

They both work good with stock pipes, the timing works better with aftermarket pipes, but still helps performance with the stockers.

 

You will notice the difference on a stock Banshee, I would also recommend getting a different head or having yours milled .030".

[mrmatt]

Will advancing the timing give me a broader powerband on the bottom end?

The advanced timing will add hp throughout the entire rpm range. Someone on here dyno tested this and showed a consistant 2 hp increase.

 

 

Timing advance will not increase your static compression, but it will increase your chance for detonation. Detonation is uncontrolled burn in the combustion chamber. This happens when the fuel/gas mixture becomes so hot that it ignites on its own, not as a result of the spark plug firing. Hot spots in the combustion chamber, such as carbon build-up or sharp edges on the piston crown can act as ignitors for the fuel/air mixture. Advancing timing increases your chances for detonation because it can cause higher temperatures and pressures within the combustion chamber, since the spark happens while the cylinder is still on its compression stroke. As the cylinder fires, all of the fuel/air does not burn at once, a flame front is initiated at the spark plug and moves through the combustion chamber. As it does, the pressure and temperature of the unburned air/fuel increases. Since ignition happens before the piston reaches the top of its stroke, the fuel/air mixture is also still being compressed by the piston. If the timing is advanced too much, the pressure and temperature of the unburned air/fuel can increase to levels that will cause it to self ignite in an explosion rather than being burned by the moving flame front. This explosion is detonation and if allowed to continue will result in the need for an engine rebuild.

[ledofthezep]

it is controlable and predictable.

Very much so. No regrets on my -2 arm. I'm primarily a duner myself also. Shee will handle a lot better and is much more predictable. I also went with +2+1 arms & shocks all around at the same time. It was like night/day, literally.

[MotulMonsta]

How much port work did you get done? If it's been ported for top end and you have a major increase on the top of the exhaust port, it will always be peaky. The only way to fixit is to get it re-sleaved and differnt portwork done to maximize low end power. On my shee, the v-force reeds smoothed out my powerband and gave me way better throttle response. But I run toomeys and I got mine setup for mid-top end power and that's where it likes to be ridden. I race MX with it..yeah it's a bit harder to keep it under power in the turns, but fancy clutch work keeps it in the meat.

[FoxBansheeRacing]

It is an stage 3 mx port job. I doubt I will have the timing advanced or flywheel lightened. Right now I am looking for at changing pipes and having the swingarm shortened.