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d.holmes

beta 300t4 clutch fix

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Mr D Holmes  

What clutch issue are you referring to on the Beta 4T.

 I currently have two 2018 Beta Factory 4T in my garage and recently owned a 2016 Factory Beta 4T.   

There are no issue that I know of.  

The clutch works great with the correct adjustments and oil.

The Beta PDF you attached is several years old (2012) and refers to a 2T clutch set up.

Please help us understand the issue.

 

 

 

Edited by billyt
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I wonder if we all avoided the forum areas of engine and clutch etc issues if our bikes would be more trouble free and less finger troubled. Many a sleepless night must be attributed to the dreaded ‘forum malody’ 😔🤯😖

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I have Billy’s old 300T.   I use the same oil he used- the only time I have any issue at all is when initial cold start. Unless I let it idle and warm up quite some time- the clutch is sometimes ‘stuck’ and I have to ride with it pulled in and brakes on a bit to unstick it.

I attribute it to the much colder weather than what he has- a lighter oil could solve it, but it works so well the rest of the time I just keep using the same stuff. It only does it after parked overnight or longer. Not a big deal to me.

Mark

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Guys  Lets not start comparing the Beta 2T clutch to the Beta 4T clutch.

Thanks for chiming in Mark (LOTUS54).  Mark lives in the north west of the USA, I live in the southwest USA.

Mark still uses the type of oil I ran in the bike when I sold it to him.

The temperature extremes are vast.  I ride in summer highs about 110F and winter lows about 60F.

Mark sees maybe 80F in summer and 30F in the winter.

While we can all debate what oil is best for our clutches in a 2 stroke a Beta 4T oil has to be selected to protect the running gear i.e. valves, top end chain etc. 

The clutch perfomance comes second in a Beta 4T oil selection.  One can imagine the engine temp in a Beta 4T when riding a 100F, if you don't carefully select an oil to protect the top end you WILL have top end problems.

Caveat to protecting the top end on a Beta 4T is that you have to live with how it make the clutch feel and behave. Or if you have the knowledge and pateince start experimenting with an oil that works for both top end and clutch.

It is a compromise. No amount of cleaning clutch fibre plates will protect the Beta top end running gear from mechanical wear due to wrong oil selection based purely upon how the clutch feels.. 

With a two stroke your oil selection it is usually witnessed/judged by an immediate clutch feel. You have no idea how it will affect the main bearings etc for a long time.

With a Beta 4T engine oil selection clutch feel will be tested quite quickly and judged good or bad. You will also learn in a rather short time how the engine oil selection has affected the top end

I have owned MANY Beta 4Ts and through careful trial and error found an oil that calms the top end down makes it whisper quite and pulls the heat away from the clutch providing a more consistent non drag clutch feel. 

The oil weight in Marks bike is more suited for the high temperatures seen in the southwest USA and not the vastly cooler temps seen in north West USA.

Hence why he  feels some clutch drag upon an initial cold start up.

I have never experience clutch drag in a Arizona winter or summer with the same bike and same oil that is in Marks bike currently.

Mark is going for top end protection and lives with a little bit of cold weather start up drag, and then it settles down.... smart man.

Re-setting the valves and top end engine repair on a Beta 4T is a bear of a job as one has to take the engine out of the frame to set the valves etc.correctly.

I won't say the brand of oil I use but rather give its weight 15/60 4T engine oil made for extreme race competition clutch and top end protection.

It has also provided the smoothest clutch engagement and hook up I have ever experienced on a trial bike.

In normal or high temperatures there is never any drag not jumping from start up.

Take what you want from this post. Believe it or not, does not change my experience nor belief.

Mark is my witness in how the bike runs with the 15/60 0il.

Respectfully

BillyT

 

 

 

 

 

 

 

 

 

Edited by billyt

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The issue is starting in gear too much drag.I have the thinner plates coming. And yes good oil is a must to save the engine.The Beta 300 t4 is a great bike. Thank-you for your kind help.

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Hi

Why would you start the bike in gear?  Most trials clutches will drag when started in gear regardless of brand....

Is this your first trials bike?

No worries, lots of knowledgeable people on here to help out with technical queries.

BillyT

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Hi,

In my Beta 300 4T (16) I had a very dragging & sticking clutch with recommended oil by owner's manual (synthetic 10W50).  Was difficult change gears and, even, the bike creeped forward fractions of seconds before the clutch were free.  I systematically tried several (much!) configurations/oils and, finally, found that  a set of sherco fiber plates and synthetic 10w40 (Repsol) were perfect to me.

I ride in south Spain (a climate similar to BillyT).  In trials use (not a sustained ride) I feel better the 10w40 because it goes faster to everywere and make its lubrication and refrigeration jobs better than a thicker oil.

Honda, in their works machines, uses 10W30 for engine (their clutch runs apart in different oil).  A thicker oil is not always better.

Cheers

JM

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Since the 4t uses all 3mm “thick” plates you can use the kevlar plates from Barnett.

301-35-10012

Hey Billy, I have a set collecting dust. Wanna try them out?

Edited by dan williams

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Please note that I am a retired heavy duty mechanic and have been riding trials for over forty years and have owned, repaired and maintained a few trials bikes.

I ordered thinner clutch discs. Part #1343310-000, which are 2.70 mm.  I measured all the clutch discs on my bike and they ranged from 2.95mm to 2.98 mm. I replaced the two thicker ones with the new, thinner plates and now the clutch pack is .55 mm thinner. This enables the clutch to fully disengage and start in gear without dragging.  Also starting from cold and only running the bike for 30 seconds can put it into first gear and it doesn't jump forward.

In my opinion this greatly improves the performance of the bike. I appreciate all the information and help from everyone and hope that my suggestion will help. 

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Cool, one more data point of clutch tuning. I think you're the first to go thinner plates on the 4T. On my 2Ts I do the clutch fix and run six of the thinner plates with 3mm step washers. That's my recipe and I'm sticking with it.

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DSC05361.thumb.JPG.aa10635612224b770714a98fe9018a87.JPGPlease note that I am a retired heavy duty mechanic and have been riding trials for over forty years and have owned, repaired and maintained a few trials bikes.

I ordered thinner clutch discs. Part #1343310-000, which are 2.70 mm.  I measured all the clutch discs on my bike and they ranged from 2.95mm to 2.98 mm. I replaced the two thicker ones with the new, thinner plates and now the clutch pack is .55 mm thinner. This enables the clutch to fully disengage and start in gear without dragging.  Also starting from cold and only running the bike for 30 seconds can put it into first gear and it doesn't jump forward.

In my opinion this greatly improves the performance of the bike. I appreciate all the information and help from everyone and hope that my suggestion will help.  This one of are trails 36 km. and 8 hours riding 6000 feet up.

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