Replacement carbs?

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Jon V8
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Re: Replacement carbs?

Postby Jon V8 » Wed Apr 20, 2011 3:08 am

FM350 wrote:
Jon V8 wrote:I think in many cases it is down to form over function,people believing their bike cant run properly unless it sports a flat slide Mk2 etc.
Yesterday I rode a classic trial on my HT5,running a mk1 Concentric - it runs perfectly a real pleasure to use.Looking around at other bikes there were allsorts of carbs,old and new.I notice that the Dellorto's with clear float bowls seem popular on Cubs and Bantams now.But then those are the two bikes that seem to gain most from a carb change.A couple of other HT5's were running the Villiers carb,but not doing anything different to mine.
Apart from the fact that in most cases you cant see it,I think the ignition system is what makes most difference,a reliable spark under all conditions can be hard to gain,wheras most carbs can be made to do a reasonable job unless totally worn out as already stated.


Have you tried a modern carb on your HT? They do make a great deal of difference, and this is the main reason top runners in UK "P65" events have Jap internals fitted to Brit carb bodies.

No,I'm perfectly happy with the Concentric as I said - it runs perfectly,down so slow you think its stopped.The give it just a little whiff of throttle and its away again,wind it on and it will pull your arms out of their sockets.I dont see how it could be any better than that really,it is a treat to use.(Plus generally starts first kick too.)
My TY250's still both run their original carbs,both run absolutely fine,start easily idle steadily and have clean pickup with no four stroking etc - cant ask any more than that.
Like most trials riders,its the rider that needs to improve - the bikes are fine.



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Re: Replacement carbs?

Postby FM350 » Wed Apr 20, 2011 6:50 am

If you get the chance Jon try a Brit bike fitted with a well set up modern carb.............the effect is a bit like using an up to date ignition, rather than a BTH mag.



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Re: Replacement carbs?

Postby FM350 » Wed Apr 20, 2011 6:56 am

David Lahey wrote:Stu it depends on the way that the rules in the MOMS for Twinshocks Class are interpreted.
Earlier this year I made a few suggestions through my club for clarifications of a few issues relating to Twinshock Class that could be included in the 2012 MOMS, and one suggestion to remove carburettors from the list of regulated parts for Twinshock class bikes. If that happens, then there will be no problem using an OKO carby next year.
With the 2010 MOMS, it is possible that if there was an eligibility scrutineer at an MA trial, having an OKO carby on a bike in Twinshock class might be a stumbling block.
Have you tried the OKO out yet? I'd love to know what you think of it on the TY250.


Very sensible.............seems a shame that lack of commonsense here in the UK regarding older bikes, means that its commonplace to spend £10k+ on "P65" bikes, with much of the spend going on modern parts made to appear like authentic items!



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Re: Replacement carbs?

Postby Jon V8 » Wed Apr 20, 2011 7:18 am

FM350 wrote:If you get the chance Jon try a Brit bike fitted with a well set up modern carb.............the effect is a bit like using an up to date ignition, rather than a BTH mag.

My Lucas mag is doing its job nicely,(Shouldnt tempt fate eh ? )was talking to another HT5 owner on sunday who was not overly happy with his BTH electronic mag having had more than one problem with it.
If you are who I think you are - will we see you at the next Bath trial on a Fantic ? 29th May,details on our website.



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Re: Replacement carbs?

Postby FM350 » Wed Apr 20, 2011 3:38 pm

Sorry Jon I thought your earlier post on this thread suggested you had fitted a modern ignition to your HT. I guess its a matter of horses for courses though, and I doubt very much Neil Gaunt will be using an unmodified British made carb in Scotland this year!



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Re: Replacement carbs?

Postby brownie » Fri Apr 22, 2011 5:35 pm

I think I've found the answer
Picture 6.png



Jon V8
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Re: Replacement carbs?

Postby Jon V8 » Fri Apr 22, 2011 6:06 pm

Excellent ! I've got a similar setup covering the throttle body/injector on me Ariel. :mrgreen:



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Re: Replacement carbs?

Postby FM350 » Mon Apr 25, 2011 4:03 pm

The main things about fitting a properly set up modern carb to an older bike is firstly that it improves performance, and secondly is something that anyone can afford (OKO carbs available from £50 in UK).



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Re: Replacement carbs?

Postby Tee-Why » Tue Apr 26, 2011 1:37 am

FM350 wrote:The main things about fitting a properly set up modern carb to an older bike is firstly that it improves performance, and secondly is something that anyone can afford (OKO carbs available from £50 in UK).


I doubt the $50 pound carb would come jetted and setup for a particular trials bike? I know that you can get a basic carb on evilbay cheap as, but through the OKO distributor here they are a lot dearer, but come all setup for your bike. I think its the same in the UK as well through a well known advertised UK business that does the same, cant quote an exact price, but I think it was a lot more than 50 pound (probably at least 3x times more!). And guess what, they can supply a round bore slide OKO carby that does look authentic and still would perform better than the original, (no flat slide required really).

BTW, anyone know the longevity of these OKO carbs? Is the slide going to wear just as bad as the Amal or Bing or Kehin, as my 35 y.o. Mikuni is still just fine thanks! I mean the replacement carb must justify why you are replacing it, (apart from performance). The OKO hasnt been around long enough to prove itself for the long run, but may get someone to enjoy their bike in the short term hey.


I would rather push my twinshock than ride a modern!

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Re: Replacement carbs?

Postby OKOAustralia » Tue Apr 26, 2011 7:55 am

Subanator

nice to read your comments..much appreciated..we spent many hours testing different OKO carbs on many different model trials bike.....it was a very tiring/tedious process but well worth the effort......thanks to those people that offered their bikes for testing....

btw - have not had any complaints re slides wearing. Would like to hear from anyone who has purchased one of our carbs and found the slide to have worn prematurely..regular maintenance should eliminate any premature wear.

Regards
Denis Lovett
Proprietor
OKO Australia




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