sinnis Hoodlum Front fork oil

[Mac1508]

Hi guys,

Hoping this will likely be a simple answer that I as of yet have not been able to find, but needing to replace my front fork seals. and naturally replace the oil there in.

However Sinnis seem to be pretty poor on documentation. does anyone know how much oil to put in? or is there some way of knowing by the forks themselves?

thanks

Mac

[husoi]

You Will need the service manual to find what depth from the top the oil should be.

Alternatively, measure the oil without the springs before you drain it. That should give you an idea of where the oil should sit.

Then you can just trial and error with different amounts and decide which level works better for you.

More oil means stiffer suspension

Less oil means softer suspension.

 

You will need to know also what w value you will be using.

Again this is more a personal choice than following the manufacturer specs.

Higher Wxx also increases the stiffness of the suspension

Normally something between W5 and W15

[Mississippi Bullfrog]

And just for fun one brand's weight of oil isn't the same as other brands.  You have to find one that works for you and then stick with it.

 

I had Putoline W10 in my CBF, switched to Smith and Allan W10, totally different ride. The S&A gives a much firmer front end. 

[Mac1508]

9 hours ago, husoi said:

You Will need the service manual to find what depth from the top the oil should be.

Alternatively, measure the oil without the springs before you drain it. That should give you an idea of where the oil should sit.

Then you can just trial and error with different amounts and decide which level works better for you.

More oil means stiffer suspension

Less oil means softer suspension.

 

You will need to know also what w value you will be using.

Again this is more a personal choice than following the manufacturer specs.

Higher Wxx also increases the stiffness of the suspension

Normally something between W5 and W15

Hi Bud thanks, yeah thats my issue I have the "owners manual" and it says sod all about it, havent been able to find a "service manual" for it.

[Mac1508]

oh also, when I say teh seals are borked...they are leaking all over the place, so if I were to measure what is in there now, it wouldnt be reliable as I have left a lot of it on the roads

[RideWithStyles]

Glad to see tou guys are learning and passing it on.

 

as husoi and MB said that is one option with the assumption of none of the old fluid has not been lost, contamination, or if even filled correctly in the first place which with these bikes i wouldn't count on.

 

The quality of the oil from the factory is low on most bikes let a lone a budget one on mass manufacturing.

if its a elmusion fork and not a cartridge its thinnest grade will be 10w but thats with the assumption of a very small light weight asian person mostly sticking to below our average speed on roads, so you can go thicker to compensate it, tyre wear will confirm if this is so.

 

so the spring is removed and the fork pushed down, you can just add the amount of oil if you know what that is and bleed it but working the fork to suck the oil into the valve but then you measure the air gap from the rim of the fork down to the level its at inside as in mm while the fork is at its lower level.

 

so ill use a cbf125 as its most similar for an example:

Front fork 115mm travel.

Fork oil book 10w at 146 cm3, different manufacturers 10w level 155 - still Too soft &springy.

Now fuch 20w at 167 much better.

Now to be clear this is an example not to say that yours will be the same, so follow the instructions below.

 

the old school way is to physically bounce test it when its filled,bleed, spring in and cap back on.

fork leg off the bike, smear a small ring of vasaline/ light grease near the seal.

standing it up just infront of your legs but between like playing gold with a putter, bearing over it with your hands and lower stomach ontop of the fork, with you upper body weight and flexing your knees, push down very forcefully once and let it return( pushing you back up with little resistance from you). did it hit the bottom of the fork travel? this is where the ring of grease that got pushback will tell you..how far is it?

if the ring got to 115mm from a 115mm travel fork - add oil, if it got to say 60mm remove fluid. ideally you want is it to be within 5mm of the travel or just kissing the bump stop of the fork.

Edited March 18 by RideWithStyles

[Mac1508]

15 minutes ago, RideWithStyles said:

Glad to see tou guys are learning and passing it on.

 

as husoi and MB said that is one option with the assumption of none of the old fluid has not been lost, contamination, or if even filled correctly in the first place which with these bikes i wouldn't count on.

 

The quality of the oil from the factory is low on most bikes let a lone a budget one on mass manufacturing.

if its a elmusion fork and not a cartridge its thinnest grade will be 10w but thats with the assumption of a very small light weight asian person mostly sticking to below our average speed on roads, so you can go thicker to compensate it, tyre wear will confirm if this is so.

 

so the spring is removed and the fork pushed down, you can just add the amount of oil if you know what that is but then you measure the air gap from the rim of the fork down to the level its at inside as in mm.

so ill use a cbf125 as its most similar for an example:

Front fork 115mm travel.

Fork oil book 10w at 146 cm3, different manufacturers 10w level 155 - still Too soft &springy.

Now fuch 20w at 167 much better.

Now to be clear this is an example not to say that yours will be the same, so follow the instructions below.

 

the old school way is to physically bounce test it when its filled,bleed, spring in and cap back on.

fork leg off the bike, smear a small ring of vasaline/ light grease near the seal.

standing it up just infront of your legs but between like playing gold with a putter, bearing over it with your hands and lower stomach ontop of the fork, with you upper body weight and flexing your knees, push down very forcefully once and let it return( pushing you back up with little resistance from you). did it hit the bottom of the fork travel? this is where the ring of grease that got pushback will tell you..how far is it?

if the ring got to 115mm from a 115mm travel fork - add oil, if it got to say 60mm remove fluid. ideally you want is it to be within 5mm of the travel or just kissing the bump stop of the fork.

oh wow ok thanks gonna have to read through and make sure I understand all that. Thanks for your sage wisdom. Will no doubt come back if I get lost thanks again

[husoi]

Instead of the grease I use a small cable tie not to tighten, just enough to move and stay in place.

 

Both forks obviously 

It works a treat

Edited March 18 by husoi