Keihin FCR or Mikuni TDMR

Hi All,

First off I would stick with my stock 38mm carbs for now as I'm going to be running a stock 900ie lump in my Monster to get it on the road and later on return to a carbed but 944cc lump so don't immediately need flat-slides. Unfortunately the CV carbs are totally shot with all rubber seals perished and to make matters even worse the air screws are rounded off and seized in which to fix would leave me with roughly a £300 bill to put right.

Along with my longer term engine plans I will also be running the following upgrades from day one;

Silmotor headers & open cans
MWR air box filter lid
Lightened flywheel (not sure if this will fit the IE lump though = ??)
Exactfit coils

Because I have knackered carbs and some performance upgrades already I've decided to go with flat-slides now but cant decide between the two brands. So far I've come to the following conclusions;

Keihin FCR 41mm - common / tuneable / no choke - approx. £1500

Mikuni TDMR 40mm - uncommon in UK / apparently less tuneable / retains choke - approx. £1000

I know the FCR's are good but expensive, however does anyone have any input on the TDMR's?

Thanks - Ben

[Kato]

Plenty of TDMR kits around and are a good carb very much fit and forget, but as you have already discovered not much info on them, back in the day only Suzuki favoured Mikuni on their race machines everybody else went with Keihin, that in itself tells a story.

They are good very reliable and stay in tune way better than an FCR easier to setup but they don't give the same sharp power delivery also they don't give that lovely noise you get from properly set up FCR's, don't expect to find massive amounts of good tuning tips/tech info on them because it does not exist unless you can speak Japanese or American as they are very common upg on Hardley's

Useless bit of info Mikuni sizes are always even 36,38,40mm
-----------------------Keihin are odd 39,41mm

Depending on what you want from your motor ?

Should you wish to ring every last horse it has to offer then FCR

If your going for modest performance upg the TDMR's are a good choice, smooth reliability with performance upg, way better fuel efficiency, just a better all round carb then the stock 38's, plus as you say you get to keep your choke and save a few quid

Thanks for the update! I did not know that the TDMR was such a soft upgrade and assumed flat-slides all gave a similar boost in performance. As I want to be able to accommodate a big bore kit at a later date it makes me lean towards the FCR's at this stage.

Wish I could find a set for sale second hand some where!

[Kato]

They are by no means a soft upgrade, and will work very well with the 944, what I meant was they are a good carb just not the all out race proven unit the FCR's are.

Hmmmn not sure now which way to go = ???

[Darren69]

Keihins will be more available I would think. Can't you get a set of 4 and split them and make 2 sets? There are a few on ebay. You'd have to buy the Ducati fitting kits I suppose but may be a cheaper option

Cheers - I've emailed a few companies but not heard back yet...

Allens down the road from me are suppliers of both brands but are top of the tree when it comes to price.

Mikuni at Allens approx. £1100 + VAT

Mikuni at Allens suppliers in Germany approx. E 940 - they wont supply the UK as Allens are their agents here...

Might buy some FCR is USA and get shipped via family but trouble is would probably get stung for import taxes.

[Kato]

Nothing to stop you spending £30 with easyjet to make a purchase in Germany

Originally Posted by Kato

Nothing to stop you spending £30 with easyjet to make a purchase in Germany

Only feeding my dog! But yeah a sensible suggestion

[jerry]

what about lectrons ,, very simple and tunable and very reliable ,,

Originally Posted by jerry

what about lectrons ,, very simple and tunable and very reliable ,,

Never knew they were available for Ducati's only ever heard of LC's running them

[jerry]

Originally Posted by Nottsbiker

Never knew they were available for Ducati's only ever heard of LC's running them

I used them on HD sporters with spectacular results ,, just fitted on to my mates old 1340 shovelhead

I reckon a pair of 38mm lectrons would work really well on a ducati , inlet mahifold runners would be the only mod and air filters ,maybe a support bracket

they are also used on a lot of jetskis and snow mobiles

[utopia]

I have a kit comprising a pair of FCR39s and the associated fittings awaiting fitment.
It might be a while before I get round to doing that.
In the meantime, I will have the carbs and all the bits (inlet stubs etc) to hand, should you wish to check on exactly what's necessary to convert a bank of four carbs to suit a monster.
I wondered about doing exactly that myself, but then I got a deal on a kit just before the post-brexit price hike.

You could try "Exige" on the other forum.
He's an agent for Chris Kelley / Cal. Cycleworks and sells their exactfit belts.
I'm pretty sure he could source the FCRs too.
I doubt the price would be much different tbh, but if you don't ask .....

Cheers Utopia - I'll make contact with Exige as I've bought starter cables and exact fit coils from him previously and been very happy with the service

[Dukedesmo]

I don't think Ca Cycleworks deal in carbs any more? Pretty sure I read somewhere that they weren't anyway...