do you need a hole in oil slinger lifan140 any gear?

[Cactus Jack]

i just put a inner rotor kit and lightened oil slinger in my bike and it runs fine but i just got told that you have to drill a little hole in the oil slinger is that true?

The thread is about ...... [do you need a hole in oil slinger lifan140 any gear?]

blingpit said he was told that you HAVE to drill a little hole in a lightened slinger which is NOT true .........

Mountain and I .... made a joke of it basically stating NO .... then 1fiftywheel cut in and had a go at us about our comments so we just had a go back him ........

I still stand by what I said tho' .... drill the hole and start looking for a new crank ...... The pics he's posted tend to back that up ..... LOL ...

Who says that Lifan's got it right ????? The only function I can see the hole performing is either as an air bleed for start up or pressure relief ......

It's very well known that for heavy duty use ...... you want to INCREASE oil pressure to the crank .. so pissing the hole off would help to achieve that .....

As for crank breakages ..... They tried to run lightened alloy hubs in place of harmonic balancers on sprint cars in the US and copped a sudden spate of busted cranks ..... so they went back to heavier balancers ..... and the breakages stopped ..... what the racers did was fit special balancers with clutches and inertia rings so that there was enough weight to dampen harmonic vibrations .... yet allow the added weight to slip under acceleration to still give quick throttle response ......

What causes the cranks to bust is the fact that the harmonic balance has been altered by the lightened flywheel ......... the lighter flywheel vibrates off axis when it reaches its resonant frequency and transmits vibrations right thru the crank to the other side ........ Takegawa has even fitted a ball bearing into the flywheel cover that the end of the crank goes into to stop the flywheel from "orbiting" and getting " scratched" ....... the word "harmonic" balance simply means everything operates together in harmony .... when a crank fails .... it's quite obvious to all that the harmony was somehow upset or unbalanced ...

When you alter the flywheel weight ...... the entire crank assembly should be spun up to the revs it's going to be used at in a balance checking machine ... to see how it functions .... then alterations made until it spins smoothly at the critical revs it's going to be operated at ..... Most people simply take the gamble that the chinese IRK rotor is balanced ....

Altering even piston weight , compression etc (the exciter force) and revving the engine harder than stock can cause the crank to break ........

 

[Cactus Jack]

Haha you guys got "DRILLED" with this one,
Sometimes its best to just listen when people have something to say, instead of trying to think you know everything all the time

You sound like a hyena in the back ground ..... I can recall you asking me silly questions about ring seal and other things .....

Someone who "thinks" they know everything would be on every thread , day in day out trying to get their post count number up .......

If you read properly .... 1fifty1wheel commented on how we didn't give enough info , he said he thought this was an "informative" site .... so we added some "info" ......

Looking at it from another perspective ..... what do you think would happen IF blingpit drilled his lightened slinger ..... then his crank stuffed up ....... He'd be going around telling people that he got messed around with misinformation from those "idiots" on Mini Riders .....

Here's an engineering drawing showing the oil flow pathway thru a horizontal engine . Dark is the pressurized galleries and dashed with arrows is the bleed off where oil escapes . Note there's ZERO bleed off shown anywhere from the slinger !!!!!!!!

 

[pitmaster]

Originally Posted by Cactus Jack
Well stop talking out of your butt if you don't know the true facts or have pics to prove you're right ......... Honda XR's don't have a hole anywhere in their slingers and they rev reliably to well over 12,000 rpm .....

Than why go back and delete this from you reply yesterday,

Who cares now anyway, somepeople always like to be right

 

[Cactus Jack]

Than why go back and delete this from you reply yesterday,

Who cares now anyway, somepeople always like to be right

I removed it just to be peaceful ...... but I note that you're all from SA .... Some people like to argue against common sense ... Hole in slinger ... busted crank ...