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New for 2012| Honda & Fantic Twinshocks | Fatbar Yokes| DC Inductive Ignition
Classictrial 28mm OKO
fitted to 325 Bultaco
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Carb upgrades:
We are now able to supply the excellent OKO flatslide carbs, perfectly set up to
suit many different trials machines, and these come fitted with appropriate jetting,
needles, and slides, as well as any special purpose adaptors required to allow fitment
to machines fitted with Amal, Bing, Dell-
As well as the OKO we are also pleased to supply Keihin and Mikuni carbs, which are again perfectly set up for your specific application.
Contrary to popular belief fitting an alternative carburetor, is not merely a matter of looking for the cheapest price on Ebay, as there is always a very real risk of engine damage if you choose to use an improperly set up carb………..in effect it’s a bit like buying a 14mm spark plug, with the idea that it must be right as the thread in your bikes cylinder head is also 14mm!
Finally in regard to Trials carburetion it is worth remembering that if there are noticeable signs of wear on your throttle slide, that in most cases the carb body itself is likely to be badly worn and this will need to be either sleeved or replaced, before accurate fuel metering can be achieved.
Chassis alterations:
For some while we have offered chassis upgrade work on Fantic and Honda machinery, and many customers have already benefited from the better handling, and much improved overall performance provided by Classictrial alterations. Unlike others who are now claiming to be able to carry out this work, all of our modifications have been tried and tested in serious top level twinshock competition.
Our chassis alterations helped Phil Wiffen riding his 300 Fantic, to win the ACU “Traditional” twinshock championship in 2008, and in 2009 Ian Baker is doing very well in the same series of events riding a Classictrial modified TLR200.
In addition to chassis upgrades alone, we can provide chassis upgrade kits for Honda and Fantic, which are inclusive of steering geometry changes, footrest position alterations, frame and ancillary parts blast cleaned then powder coated, as well as one of our lightweight GRP fuel tanks in customer specified custom colour scheme.
Classictrial Fantic chassis upgrade kit
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Alloy fuel tanks:
Top quality aluminium fuel tanks for classic bikes are items that are extremely difficult to find. We have looked at this very carefully and have initially designed and manufactured a very special aluminium tank to fit 200,240,300 Fantic twinshocks. While being quite costly in comparison to the various budget alloy tanks currently available, these tanks may well appeal to anyone wanting to stand out from the crowd, and have something that’s hand made to extremely high standards fitted to their bike.
Our alloy tanks are made to aircraft standards and can be supplied with either a conventional billet alloy screw cap, or a very special flush fitting cap, designed specifically for off road applications. Depending on levels of interest, we may also be able to produce similar alloy tanks for other classic machinery. The tank pictured is a prototype that will be fitted to the very special Fantic, Phil Wiffen will be riding in the 2010 British twinshock championship.
Classictrial pre-
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Competition forged pistons:
Cast pistons are very commonly used in an engine primarily to reduce cost, and do work perfectly well in many different applications. However in nearly all serious competition engines, forged pistons are specified as they are stronger, longer lasting, and more durable than the equivalent cast parts.
Bearing this in mind, Classictrial has developed a range of forged performance pistons for Fantic trials machines. These all incorporate detail improvements over the OE parts, and are all fitted with modern 1mm chromated Wiseco type drawn steel wire piston rings, which reduce friction and provide improved cylinder sealing over a longer period in comparison to the OE nodular iron rings. Our 69mm pistons for the 212cc piston port engines, incorporate the same twin ring configuration as the later reed valve bikes which is a big improvement over the original single ring piston designs, which really require a new ring fitted every 6 months if a bike is used regularly in serious competition.
Classictrial forged 69mm competition piston for 212cc Fantic
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GRP fuel tanks:
We are currently able to offer lightweight (Fantic 1.2kg, Honda 2.5kg) GRP fuel tanks to fit all Fantic twinshocks, and the Honda TLR. These are produced using the correct ethanol resistant resin systems, and are properly post cured to ensure that there are none of the problems that can sometimes occur when inappropriate materials or production methods are used.
We can also supply high performance carbon/kevlar compression moulded Fantic tanks, which are lighter and stronger than our GRP mouldings. These higher spec parts are not designed purely to enhance the cosmetic appearance of the bike, and do require painting to provide the laminate with proper UV protection.
In regard to the TLR Honda, we are currently developing an RTL style tank seat unit for these machines, which will be supplied with a virtually unbreakable polyethylene fuel cell, and a lightweight GRP cover. These units will obviously be more durable than the GRP tanks currently available, and we will also be able to provide covers made in carbon/kevlar, which was used to make the works RTL tank covers.
Very special carbon/kevlar Classictrial TLR tank/seat unit
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Modern twinshock:
Twinshock trials is starting to become increasingly expensive, with cobbled up “restored” examples of the more popular machines already being sold for ridiculously high prices.
Primarily to increase accessibility to the sport for those who cannot or chose not to spend £2K + on one of the more competitive bikes, we will be showing exactly how to convert a rather down at heel £360 Fantic 245 monoshock, into a usable and reliable twinshock. While not being anywhere near as competitive as an original twinshock, that has had thousands spent on it, this bike is likely to provide just as much enjoyment to its rider as an original machine costing 2, 3 or maybe even 4 times as much. In the meantime we would be pleased to assist anyone who perhaps has more sense than money, and who would like us to help them with building a modern twinshock.
We will also be able to provide twinshock Yamaha TY250 mono, and Fantic 05 series (205/245/305) frames on an exchange basis, which may be helpful for anyone wanting a modern twinshock, and not able to do the work required themselves.
Yamaha TY 250 modern twinshocks (2 for sale from £1000)
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Future developments/projects
Polyethylene fuel tanks:
As well as a special moulded polyethylene fuel cell for our proposed new and improved TLR Honda tank seat units, we have been carefully investigating the possibility of making complete replacement tanks in this material. These may not interest the type of customer who is prepared to spend 500 Euros on a Spanish made carbon look copy of one of our existing Fantic fuel tanks, but may well be just the thing for anyone looking for something that is highly durable and relatively inexpensive. There is a possibility that we may be able to supply these in a plastic which can be easily painted by our customers, or simply in natural plastic, which will mean it’s possible to see how much fuel remains.
Polyethylene micro light fuel tank
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Fantic exhaust back boxes:
All of the Fantic twinshock bikes work extremely well with a modified straight through MX back box fitted. However these need to be of the correct core size, and do need alterations to the intake pipe and mounting brackets. Obviously not that many people can carry out this type of work, so we have produced press tools in order to manufacture a very special 300 style Fantic back box, which will fit all the twinshock models.
On the 300 Professional we would suggest repacking the front silencer for best results,
and on all models de-
Classictrial modern twinshock build:
Having noticed a replica type frame kit to accept Honda running gear listed on Ebay for a start price of £1.8K, we wondered if it would be possible to build a complete and extremely capable modern twinshock, for less than the start price of the Honda frame kit? There is no real concern as to whether those that welcome £10k Brit twinshocks being ridden as “P65s” yet have problems with slightly modified twinshocks, approve of this bike or not. It’s going to get built simply as an example of what can be achieved without spending enormous sums of money, and very possibly ending up with a very shiny collector’s item, that’s never likely to get used seriously.
Our 315R chassis came from Ebay for around £20, the Sherco swinging arm was about £30, the shocks are well used Falcons that were bought several years ago, and the motor will be based on a £60 Ebay buy, which had broken rear engine mountings. Forks will be Gas Gas again from Ebay at £125, probably a Rev 3 front wheel that was £100, and a Fantic section rim laced to a 125mm Grimeca hub which cost £100. So for less than £500 we the basis of what’s going to be needed to build a twinshock that’s going to be cheap reliable, and most importantly a lot of fun for anyone to ride against far more sophisticated and costly modern machines.
Montesa mono frame for a Classictrial modern twinshock
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Please feel free to contact us for further information on anything mentioned above, or for general help and advice on anything to do with your twinshock or P65 trials machines. Email us at classictrial@gmail.com or phone Chris on 02380 600 850 or alternatively 07761 971 756.
Other recent developments
Prototype TLR tank unit
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