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dmc2028372

4Rt Engine Oil. Help!

27 posts in this topic

Evening all. Got my 4rt on it's side and it filter out. Her indoors went to the local road bike shop and picked up a litre of oil.

She came back with silkolene gear oil light sae 75. On the back it says gear oil for wet or dry clutch transmissions. Crankcase rating sae 10W/40. Is this right. Chap in shop said it was the right stuff?????

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It will do in the gearbox but totally unsuitable for the motor.  Nip to the Tesco forecourt and get a litre of Castrol fully synthetic bike oil.  Can't remember the full name, and can't get to the oil cupboard to check,  but folk on here recommended it and for some strange reason Tesco are a fraction of the usual price.

 

Just checked posts - think it was Power 1.

Edited by 2stroke4stroke
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Yep, silkolene gear oil light sae 75 is the right type of oil for the gearbox, it's the same kind of oil as the prescribed Elf HTX 740.

 

Any good brand 10W40 motorcycle oil will do for the engine, but I also use the Castrol Power 1

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Yep, silkolene gear oil light sae 75 is the right type of oil for the gearbox, it's the same kind of oil as the prescribed Elf HTX 740.

 

 

No it isn't.

 

The clutch will scream and judder.

 

The only oil that works properly in the 4RT gearbox is Elf HTX 740 and unfortunately it's getting harder to find. It's also very expensive when you do find it.

 

Loads of threads in the Montesa forum about this.

 

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Do not put the Silkolene gear oil light SAE 75 into the engine side.  

 

The 4RT uses 2 different oils, 10w40 motorcycle oil in the engine side and Elf HTX 740 in the gear box.  Silkolene gear oil light sae 75 would be an alternative to the Elf HTX 740 but unless you have changed out the clutch pack with an aftermarket version you will likely not enjoy the result.  

 

best of luck.

 

 

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I have used and recommended the Silkolene Light Gear oil for over a decade and have never heard of any problems with it in the gearbox. The engine part needs a good 10-40 motor oil. It only takes about half a liter so buy something good and change it often. 

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No it isn't.

 

The clutch will scream and judder.

 

The only oil that works properly in the 4RT gearbox is Elf HTX 740 and unfortunately it's getting harder to find. It's also very expensive when you do find it.

 

Are you speaking from experiance with the 

 

Are you speaking from experience with the Silcolene?

 

Because I've used the similar GRO Gear Extreme 75W light gear oil  and it's even a little better than the Elf oil.

 

By the way, look at the specs of the different light gear oils, they are very similar.

Edited by guys

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NO ! NO! NO!....

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Are you speaking from experience with the Silcolene?

 

Because I've used the similar GRO Gear Extreme 75W light gear oil  and it's even a little better than the Elf oil.

 

By the way, look at the specs of the different light gear oils, they are very similar.

 

Yes, as I said, It made my clutch scream and judder and the oil came out very discoloured after a fortnight. Elf lasts 6 months between changes and comes out looking like new.

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Not sure what was in my 09 when I got it, some sort of Rock Oil I believe and the clutch was fine. Only three trials on with the Silkolene certainly but no noises or action problems so far.

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Yes, as I said, It made my clutch scream and judder and the oil came out very discoloured after a fortnight. Elf lasts 6 months between changes and comes out looking like new.

Maybe it was a bad combination with the previous oil...

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A friend of mine has suggested that ATF will do the job in the clutch/gearbox?

 

I would shy away from ATF in a 4RT transmission myself.  

 

What the bike calls for and how different ATF is over the ELF would say there is a chance that it could cause swelling in the fiber disks and or separation of the fiber from the disks.  This isn't something I can say will happen for sure however based on the differences in ATF over ELF using something like GRO Gear Extreme 75W.  As GRO has close to the same viscosity index and is built for motorcycle transmissions instead of automatic transmissions I would think it is a safer choice.  (even then it isn't what the bike calls for so its a gamble ether way)

 

Viscosity comparison of ELF, GRO and Silkolene Light...

 

Gear Oil           | @40C      | @100C

ELF HTX740     | 21.4        | 7

GRO Extreme   | 20           | 5.2

Silkolene Light  | 100-180  | 15

Edited by jonnyc21

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I would shy away from ATF in a 4RT transmission myself.  

 

What the bike calls for and how different ATF is over the ELF would say there is a chance that it could cause swelling in the fiber disks and or separation of the fiber from the disks.  This isn't something I can say will happen for sure however based on the differences in ATF over ELF using something like GRO Gear Extreme 75W.  As GRO has close to the same viscosity index and is built for motorcycle transmissions instead of automatic transmissions I would think it is a safer choice.  (even then it isn't what the bike calls for so its a gamble ether way)

 

Viscosity comparison of ELF, GRO and Silkolene Light...

 

Gear Oil           | @40C      | @100C

ELF HTX740     | 21.4        | 7

GRO Extreme   | 20           | 5.2

Silkolene Light  | 100-180  | 15

 

 

The clutch plates aren't that fancy.

 

Outer friction plates

http://www.partzilla.com/parts/detail/honda/HP-22201-KY2-000.html

 

Inner friction plates

http://www.partzilla.com/parts/detail/honda/HP-22201-MEL-000.html

 

Steel plates

http://www.partzilla.com/parts/detail/honda/HP-22321-MG3-000.html

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The clutch plates aren't that fancy.

 

...

 

That is why I stay away from oil that is an unknown for that clutch pack, you don't know if it will swell or degrade the plates, and its not like they are telling us what they are made from so how do we know for sure what will happen?  Worst case, maybe they disintegrate because some of the oil modifiers react badly with the glue or material...  Would I expect this?  No, but anyone willing to try should at least know what the possibilities are first.

 

My 2 cents is don't got ATF as there are, from my point of view, better choices available.  

 

Everyone is free to do what they want, however I have heard and seen to many stories of people having things go wrong when doing things like changing to an automatic clutch oil when your not working with an automatic clutch, or running the wrong type of oil in forks and having the seals swell, etc.  

 

I am not against trying different options, just not willing to go way out of scope without ether a reputable source showing it works or at least being willing myself knowing that I could really mess things up.  I have even taken a leap or two myself but only when I felt I knew what I was getting into and the possible negative out come that could happen first.  

 

Ether way, have fun and do what ever you want because in the end this is just my experience mixed with opinion and in truth isn't worth much but I sure hope it helps someone.   :thumbup:

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