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84' TT600 carb advice wanted

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Hi,

 

Finished a full restoration on my 84' TT600L a while back. A few upgrades along the way too. I may post the story here when I get time.

Anyway bike starts and runs and is nice to ride but has a carb issue of some sort. Basically it bogs down really badly when I try to gun it. It's fine if I gradually roll the throttle on. The motors been rebuilt and upgraded: sleeved and bored to 608cc, Wossener 10:1 piston, mild cam, oversize kibble exhaust valves, mild porting (just cleaned up the bowls basically), OTR stainless oversize headers and a fairly open DG "O" series can in the back. It's a nice motor...

The YDIS TK carbs always had a reputation for being tricky, so I made an effort to nail their rebuild. I have an ultrasonic cleaner and used that to get them looking perfect and stripped everything down. New hoses, clips and jets, enrichment valve, O rings & seals, screws etc. With more power I fitted a dynojet kit per its instructions. (Seemed designed more for XT600's but there ya go...) Anyway the bike started OK and ran smooth down low, but hestitated from mid range on up, but with no sign of black smoke or a sooty plug. So figuring it was still too lean I bought some TK jets from a place in the USA that specialises in bike jets of all kinds. I upped the mains in the primary carb by two sizes and played with needle clip positions on both sides too. It did improve things at speed but still it bogs down badly when I gun it. It's like the primary carb's accelerator pump isn't doing it's job, or something similar. Then I thought perhaps the TK setup simply isn't up to the extra gas flow? But then being old enough to remember these as new race bikes, folks back then raced them modified some, with the standard TK carbs, so I figured maybe that's not it at all...

So do we have any TK gurus here? Not looking for wild guesses, more like ideas from guys with TK carb know how etc. My carbs look beautiful and I've done all I could do to restore and rebuild them, but I'm so tired of pulling everything apart to try and sort this problem that I've even been thinking about doing the Raptor 660 carb swap. The Raptor carbs are cheap, even new ones, and as you'd expect everyone who's done it says they Improve performance quite a bit over OEM. But by the time you buy an MP twist throttle set up and the Raptor intake manifolds it adds up. Plus I like running a proper airbox, both for looks and dirt as this bike lives off road. For sure I'd love to try have the Sudco Keihin CR kit or Keno's Mikuni TM34 set up, but that's crazy money ($700 to $1000), just to fix what should be just a tuning problem.

Any ideas? CV carb spring change? Known jetting combos for a tuned (not full race) engine like mine? Thanks in advance...

IMG_2613.PNG

Edited by mungus

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I'm no guru but I am familiar with these bikes. I have the same year as yours with similar modifications--621cc 11.5:1 JE piston, ported head with stock valves, Web motocross camshaft, K&N air filter, stock carbs with stock jetting, stock exhaust with the end cap removed from the muffler. With this combination, the bike runs like a bat out of heck. Responsive throttle, no detectable bogs and revs like a 450.

From what I've observed, the stock carbs are very sensitive to exhaust changes for whatever reason--at least on my bike.

I left the jetting stock as typically when you go up in engine capacity with the same size carburetor, you can run the stock jetting and in some instances you have to go leaner as the more CCs and/or compression creates more vacuum signal through the carb.

I swapped to an old Cobra muffler that was on the bike when I bought it several years ago it was a complete flop. I felt maybe it was a little more responsive right above idle but everywhere else it sucked. Mid range was flat and top end non-existent. It felt like the secondary carb wasn't opening.

Do you have the stock exhaust system you could install and try out?

Does the secondary slide move freely up and down with no glitches or rough spots?

Something else to check is the CDI box. Sometimes they will function and allow the bike to run but they won't advance the timing resulting in a very flat exhaust note, no power and loosing the ability to accelerate. I've had at least one do that in the past.

 

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Thanks for the ideas, appreciated. CV slide moves just fine, checked that as the first thing. Interesting idea about the vacuum signal, but then a heavier CV slide spring would cure that. Maybe it's worth trying to source one just to try it out.

Yes I've still got the OEM exhaust, albeit like yours the core has been cut out, but I won't be swapping that back. The only difference that makes is increasing back pressure and / or decreasing gas flow. Both negate the good engine work done, so a defeatist solution really. I can accomplish the same thing by restricting the can, as it's got removeable restrictors (so called DB Killers) in the back and I have a few sizes of those could try to simulate the OEM system. Or I can even make my own super restricted version as an experiment. However if that achieves anything it just goes to show that either the carbs aren't delivering enough fuel to match the greater gas flow, or that the secondary isn't opening fast enough. That would just reveal the root cause, but it's not a real solution. The trick is which thing is at fault? 

Interesting idea about the CDI unit, but my hunch is that it's not that. As this defect is not RPM or manifold pressure dependent, so the ignition curve or spark strength doesn't look to be at fault. She runs fine at all throttle setttings and RPMs as long as you roll it on gently.

If I had access to a dyno that would help solve this. Although I guess I would need to change the back tyre to run on one properly. Perhaps the Raptor carbs (or the more expensive solutions by SUDCO or Keno) really are the way to go as the TK system was a compromise to give decent economy for the bigger selling XT, it was never made for performance, and as probably just used on the TT to save cost  etc. But before I go that way I'll keep playing with these TKs some more. I've yet to see a thread on fitting the Raptor carbs that shows a really nice job being done, they've usually shown a pretty rough effort on a beat up bike, with no airbox etc. But I think if I bought the whole Raptor intake set up and a spare TT600 airbox to butcher, I could probably make a nice system in the end. The Kedo Mikuni dual 34 setup is the ultimate IMHO, allows the OEM cable and is a neat install too, but just insane money for a bike like this...

Thanks anyway, got me thinking about other possible causes. Heres a recent snap of the old girl...

TT600L finished RHS.jpg

Edited by mungus
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I have a set of the 31mm Sudco CR Specials. Had another '84 back around 1994 with the same camshaft, ported head, stock bore with an 11:1 Wiseco piston and SuperTrapp muffler. That thing was off the hook with those carbs. Never finished fine tuning the jetting though as you had to modify the fuel tank to run those carbs--the throttle cable mounts ran into the bottom right of the tank. Had a local plastic welder mod the tanks but they all 3 would start leaking so I went back to the stock carbs.

Kawasaki 250 Ninja carbs bolt right on too but you would have to mod the tank for those as well if I remember correctly.  Couple pics in my thread if you want to have a look.  

 

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Thanks, yup I've seen that thread, a couple of years back when I started my TT600 project. I think it's what first got me looking at that option. A pity about the cable issues, especially given how expensive the SUDCO CR kit is. 3 times the price of a new Raptor 660 dual carb... (< $200 USD inc postage on eBay). But then the Raptor carbs are both CV's aren't they? I guess the dual accelerator pumps make up for that.

Did you ever look at other ways of running the cable? I'll have to look at some close up photos of the CR kit install I have somewhere. I've attached some photos of a beautifully made MX purposed TT600L project, built in Italy maybe 5 years back, that had those CR carbs on it and there aren't any cables hanging out like on the LHS like all the photos I've seen of the Raptor carb installs, or fouling things up under the tank on the RHS like on some TT600 installs I've seen. The bike below bike used a YZ490 tank, seat and rear fender combo, and by the look of it the YZ490 gas tank doesn't hang down as far as the TT600. One worrying thing with the CR option is that I have already found several stories on the web of them NOT fitting without lots of work and people end up chucking the idea away, having spent allot of $$$... Just like the previous poster said he ended up doing. That kinda puts me off a bit. :-(

That's why I like the Kedo Mikuni 34 set up. It uses the stock push / pull cables, but Kedo's price is insane. IMHO way overpriced when you know how much each carb can be had for new. And what do you get for the extra $? Not much really, the small bar that bolts them together is nothing to make to anyone which basic engineering skills, and the linkage likewise can easily be done. But perhaps in high cost driven western Europe people are used to paying silly money for stuff and I suppose it's just easier to click buy and bolt them on. Personally I think dual 34's might be just a little much for anything less than a max overbored race engine.

Anyway thanks for the feedback on the CR option, I was seriously considering it as an easier way that making up my own Raptor intake system. That would require me to buy the carbs, MP throttle, pair of intake manifolds and airbox boots and a TT600 airbox to modify to take it all. I liked that they were recent stock Yamaha parts etc. And that there are web examples of the job with sample jetting etc.

I'll have to post up a project thread on my TT soon. It's a full nut and bolt concourse restoration with some useful hidden upgrades like Race Tech shock and fork internals, colour matched Eibach spring, uprated engine etc. I really like riding it, even with the weight. Sounds great too.

Twin Keihins.PNG

TT600L MX - LHS.PNG

MX project bike RHS.PNG

 

Edited by mungus
Add the TT/YZ600 photos

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Heres some photos of the 2 other options I'm checking out (assuming I can't get the OEM TK setup running right).

Kedo Mikuni TM34 set up. Total cost to me as above around $1,000 USD (BUT ITS MADE TO FIT THE BIKE, INC AIRBOX & CABLES).                                   

Its also sold by OTR Germany but not sure if their kit includes the airbox adapters like Kedo's does. Their sales link doesn't say so...

http://www.kedo.com/products/31235.html

Kedo TM34.gif

AND - Yamaha Raptor 660 set up: unbranded dual CV carbs. Total cost to me all with new parts (inc carbs) C $500 USD. (not great photos, but give you an idea)

post-446127-0-62325900-1440279639.jpg.4deff05dc9173b904b145d5f9fe9285d.jpg

 

images2EG98JYN.jpg

 

 

Edited by mungus

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One other thing I just noted. I've seen a Sudco CR installs where they managed to use a fairly stock looking airbox.  It appears to me that the problem is the top of the cable bracket fouls the RHS rear lower tank, But that looks fixable with alot of re-fabrication (cut, cranked forward and extended slightly). The cable wheel should be able to be centre cut, rotated to match the bracket, and re-welded / re-plated. But that's a lot of work, and the idle screw location would still be a problem to solve.

Also one guy is claiming his Clarke tank has a recess underneath that allows the CR kit to fit without dramas... This would be mean no need to touch the CR bracket at all. Wunderbar! I have a Clarke tank on my TT600L, so I'll go and check that claim out shortly. Heres a nice photo of the CR carbs that shows the bracket sticking right up.

Sudco Keihin CR31 Ninja 250.jpg

Edited by mungus

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Well the Clarke tank story is bollocks I'm afraid. I checked my new Clarke alongside my OEM tank and can't see any difference in that area.

I've also noted the idle screw on the CR setup would not tolerate moving the cable bracket around. Amazing considering just making the bracket bend 45 degrees forward and using an underslung idle screw (vs over the top like it is) would have made the cable fit beautifully. Why market a kit for the XT/TT family if it doesn't fit properly... Dissappointing but that's life, and a shame because they look great and no doubt work well on the motor.

One other thing is that it's advertised as being the most "complete" TT600 carb upgrade kit on the market, this despite admitting in their own blurb, that you can't use the stock airbox. QUOTE: "ABSOLUTELY NO ONE SUPPLIES A MORE COMPLETE KIT...NO ONE!"

http://www.power-barn.com/yamaha-tt600-or-xt600-keihin-cr-carburetor-kit/

Ummm well, the Kedo TM34 kit includes everything needed for the install and some tuning PLUS adapters to make it fit the stock airbox. Also the CR kit doesn't come with a MP throttle kit, which most people say is needed.  All this might explain why they are being discounted at this reseller at the moment. Just my view of course...

In my view SUDCO needs to do some homework on this product. At least change the cable bracket tilt and the idle screw position so the damn thing actually fits, and perhaps even offer some carb to airbox boots. If OTR & Kedo can manage it, why can't SUDCO?

Edited by mungus

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Nice bike you have there! So, that exhaust system is designed for our bikes? I searched and searched and couldn't come up with anything for our model year. I'd be interested in purchasing it. Where did you get it?

One other thing I had to do to fit the CRs was to remove the outboard crossbar bolts--they ran into the frame tubes. Looks like the YZ tanked bike shown above did the same.

I might look into reclocking the cable bracket on the CR carbs. I have also thought about purchasing a Clarke tank and using a heat gun to reform the area where the cable bracket resides. Don't want to screw up the stock tank.

Anything can be accomplished if you have the talent and/or money I suppose. :)

There's a guy who goes by Schrauberklaus who did a custom Mikuni installation on his Honda XL600R. Maybe you've seen it.

http://advrider.com/index.php?threads/how-to-build-dual-flatslide-carbs-for-honda-xl-xr-600.804951/

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Thanks.  I made the exhaust rear section using a rebuildable DG "O" series oval muffler from eBay and a pair of 45 degree stainless tube sections that I welded together and then swaged to fit the OTR stainless headers. There wasn't anything available as an off the shelf product that I could find. The header exit pipe and muffler tube are the same diameter so when no DB killer is fitted it's a straight through race pipe. (With spark arrester of course). A bit loud like that so I am running a slight restriction in the DB killer to tone it down a bit. I bought different DB killers so I can swap them out between trail, track or street (if I ever use it on the road, like for ADV touring).

I'd be interested in seeing your reclocking if you get it done. The bracket is easy enough I'd say, and looking at the HD photo I think you could swap that long idle screw for a short Allen screw that doesn't go past the bracket. it's the cable wheel that may be the tricky bit. Perhaps if you used a small annular cutter you could reclock the cable wheel then MIG/TIG it back together and replate it. Or maybe if you only reclock the bracket just enough to miss the tank you could get by without touching the cable wheel?  I'm guessing SUDCO just used an off the shelf bracket that fits XTs, as I can't see anyone designing something for a TT600, that fitted so badly... :-( SUDCO are a decent sized outfit and they know their products, so it's disappointing that this is all they could be bothered offering. It wouldn't have taken much to make it right.

Bummer about the frame bolt too, probably adds a little strength around the oil tank area. I'll have a look at the XR article. Thanks for the link. From what I've gathered looking at everything so far, there are only 2 practical options for my TT: 

Economical but a bit ugly IMHO - Raptor 660 carb swap using the Raptor intake manifolds and airbox tubes. I should be able to modify a TT600 airbox and the Raptors tubes to fit together as a stock style setup.  Really not interested in having a couple of foam socks hanging out in the breeze myself. Not sure about the new Raptor carbs offered on eBay. They are lovely and new and cheap, but I'm wondering if the OEM Raptor carbs are genuine Mikuni and the eBay ones are just Chinese knock offs? Or were the Raptor carbs no names to begin with?

Expensive but nice, and complete - Kedo Mikuni TM34 kit. It's the ducks nuts. All ready to fit and has been well made. But my god the price is just crazy!  €720! Are they serious?

Edited by mungus

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Wow that guy went to all sorts of trouble to fit those TM carbs on that XR! The TT600 fitting is child's play by comparison.

So it seems the dual TM34 B65 set up comes from a Raptor fitting too! An upgrade or later factory fitting I assume? Now I can guess where Kedo got the idea from. It's definitely a good upgrade over the TK set up. A proper performance set up with modern parts. Any vac sec carb set up is a compromise for economy. We use them on American V8's for just that reason. (my 68 Mustang 390 had one from the factory as did almost all V8's in the muscle car era). "Double pumpers" is what we fit when we want power and that's what the dual TM34 B65 set up is.

I have to remind myself that this is all getting a bit carried away. The bike should perform great for me if only I can get my TK carbs sorted. This isn't a race bike, it's been sensibly upgraded and has plenty of power, and we are talking quite serious money to solve what is just a bogging down problem... if I call a few wreckers and someone offers me a complete Raptor set up for cheap than OK. But otherwise I think it's back to the TK drawing board for now.

Edited by mungus

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OK, well going back a few posts where I asked what kind of carbs the Raptor 660's have. I found a free owners manual download and can now see that they have Mikuni BSR33's. Not a no name.

So given the cheapest offerings in eBay (see photo) are sold from Shenzhen in China (using the same promotional photos as the US based shops), I think it's very likely that all the new cheapies on eBay are Chinese copies. Not to say that means they are rubbish, as I know the Japs get a lot of their stuff made in China now, and these do look to be nicely made. But anyway the knowledge base is slowly increasing. Normally I'd avoid CV carbs for any performance application, but given they are bigger than the TKs and are a balanced pair with accelerator pumps (ie a double pumper setup), I'm thinking they should be good. The web posts by guys who've fitted them, say they go really well.

Remembering you have to buy the intake manifolds and airbox boots to finish the job nicely. So add $100 - $200 for that. (on that subject I note that one of the Raptor's intake manifolds is a wide oval, not round like the TT600's, so I guess you buy 2 x the round intakes and flip one upside down?). Is there anyone here whose done the job who can let us know? Likewise I've read that each carb runs different main jets for the unequal porting, (and the 3 intake valves on the 660 engine), so that would have to be put right. It looks like the carb in the photo has an enrichment circuit on the side. Great if so as that should reduce the "popping" on coasting... But I'm downloading a Raptor 660 service manual now, so that should tell me all the details about them.

However the Raptor setup does work, has parts availability and the cable routes OK. However I'd like to see some more photos of their installation on a TT600 though, as the throttle shaft / cable wheel housing looks like it sticks out a fair way, although one positive effect is that the cable is easy as to access, compared to the nightmare access on the TK's. Also no matter how many times I look I can't see any sign of an accelerator pump on the BSR33 carbs. Can anyone advise otherwise? Doesn't mean they aren't good, but helps to compare their bang for buck over the Mikuni TM34-B65's from Kedo.

But short of winning lotto I don't think I can justify €720 plus postage for the Kedo setup and for now the CR kit simply doesn't fit. So perhaps the Raptor setup is the way to go for an upgrade, unless I can get Kedo or OTR to take off the 19% VAT they have in Germany for an export sale, it's easier to justify then.

 

IMG_2619.PNG

Edited by mungus

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Sounds like you have a plan. If you do mount the Raptor carbs, please do a build thread. The ones I've seen all seem to end the same way--open ended. lol.

'68 Mustang with a 390, eh? Nice! I had a '68 Cougar GT390 car I built a 428 for using Edelbrock Performer RPM heads, Intake, Hooker Super Comp headers--those were a complete bi tch to install--and a nice Comp Cams solid lifter camshaft. With a 3000 stall in the C-6 and 3.89 traction lock in the 9", I could take off in drive and smoke the tires for as long as I wanted to stay in it--pretty much. And yes, it had a double pumper, none of that sissy vacuum secondary crap. lol.

You should do a build documentary thread on your bike. You've done a very nice job on it. The more info we can get out on the old TT600s, the better. Information is very thin for these bikes. I started a thread on ADVrider for the old USA TT600 bikes to share info and whatnot and so far I've been talking to myself.

Edited by zrxer

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Yup the Mustang takes allot of my time. Its on my rotisserie at present. Its a mostly numbers correct 68' GT390 Fastback. Like the "Bullitt" movie car. I'm building my 390 up right now. It had a C6 (R servo) from new but I've bought a Tremec TKO600 kit from Modern Driveline for it. Like manuals better, but I'm keeping the C6 and all its stuff in a box for posterity. Rebuilt/New 3.7 posi in the back. The engine is mild (street car for the family), about 380HP & 460 Ft/LBs. Bored to 402 CID, mild COMP HYD roller cam, Blue Thunder MR "PI" alloy intake, 730 CJ carb (yup its a vac sec!), FPA headers etc. Will be Bullitt Highland Green when finished. But thats another story...

As I just sold my YZ465G and IT200L (wife pressure), I decided it was time to finish sorting out my TT600. Its all done except for this carb BS. 

I've kept some restoration photos, but not as many as I should have. If I go the route of the Raptor carbs I'll be sure to photo it. Although I am struggling to see where the accelerator pumps are on these BSR carbs at present. I have a strange recollection about someone mentioning fitting FCR Keihins too. But I havent tracked that one down yet.

I used to race against the same TT600's on my KDX when I was about 16 or 17 yo. Kinda funny that I'm riding one myself now...

Edited by mungus
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Well I found it, here is the link for a shop selling a dual FCR-H-39 kit for TT600's. $1,199 though! Wow... And the listing doesn't even say what comes in the kit or have any info really: i.e. do they come with or need adapter manifolds? OEM cables OK? Do they come with an airbox adapter? Given that the Kedo TM34-B65 kit comes with everything needed for $200 less, (and they are both modern flat side pumper carbs) I'd be a bit bummed out if these guys said "heres ya carbs, ya on ya own for fitting dem bud". I emailed them to see what they say is included.

http://www.keihin-fcr.com/index.php?route=product/product&product_id=148

I think out of all the options these are probably the coolest looking and highest tech (roller slides etc). And I know FCR-H carbs are pretty hot property in the racing scene, but for that kind of money I'd expect a complete kit, or at least a bunch of jets and some hose & clips. I do like the inboard cable bracket though, out of the way but still accessible. Its a nice set up, carb wise.

 

FCR-H 39 DUAL-500x500.png

Edited by mungus
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Well I got a response back.

All you get for the $1,200 USD is the carbs, nothing else. No jets. No adapters. Nada!

The shop says their FCR-H-39's use the OEM manifolds and cables. So in my case I'm looking at $1,200 USD + whatever airbox tube adapters they may (or may not) have + postage. I think unless you are building a mega bocks full on race bike, these are just nuts. Very nice looking nuts mind you!  Given my bike's engine is only mildy uprated and won't be used by me for racing (too old, I'm afraid at 50 my VMX & Vinduro days are over) its simply not worth it.  And the rub with that is that (at least here in OZ anyway), these FCR carbs would be illegal for VMX or Vinduro. So I'm thinking this is really only useful for guys making Motard specials or aiming for the ultimate restomod to make folks go oooh aaagh in the Forest carpark.

Nice to look at though and I bet they make it go...

 

Edited by mungus

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So heres the comparison I came up with, maybe it will help other folks pondering a TT600 carb fix? 

Option 1 - fix my TK carbs problems (hopefully I can, but its a dark art thing here, as I've already changed jetting multiple times etc). Cost? Maybe couple of hundred if I take it somewhere that has a dyno. I doubt the average shop mechanic will know much more about 1980's TK's and would probably just waste my $ guessing without a dyno to ID things. The end result would be a nice running bike, but not much faster than stock as the TK's are always going to average (Vacuum secondary & no accelerator pump). This carb was never made to perform, is a pain to work on and parts are scarce. But its OEM, so as these bikes get older its what people want to see, and its Vinduro legal for pre 85' class. As my carbs are already fully reconditioned, lets say $300 AUD for labour, dyno + a couple of jets.

Option 2 - Hit eBay and put together a BSR33 (Raptor 660) kit. That includes; 2nd hand OEM carbs + rebuild kit, pair of 2nd hand Intake manifolds, pair of 2nd hand airbox boots, (will be modified to fit the TT600K/L/N airbox, Motion Pro twist carb kit PN 01-0056/01-0738 (new), approx 4 pilot & main jets to tune and equalize the carbs (I have some anyway but ya never know). If one shops around the boots and manifolds can all be had with all the OEM hardware, none of which comes new or with aftermarket stuff. I'm guessing I may need to buy a another LHS manifold as the stock RHS one is a funny shape for the 3 valve intake on the raptor. But I would hold off doing that until I've trial fitted them. The new Chinese knock off carbs might be OK and of course they look great, but I can source tidy OEM Mikuni carbs for less and I have everything needed to recondition them to as new.  just trust them more is all. Chinese is still Chinese. Total cost I've figured out is around $500-$600 AUD, depending on how many new parts the carbs need. 

So this option is expensive compared to fixing my TK carb's problems, BUT I get newer tech and bigger throats, more power and easier tuning. All good stuff. The downside is (to me) the LHS looks ugly with that fat cable wheel housing, and the time it will take to get it all right, I'm guessing maybe 10-20 hours of my own labour. 

Option 3 - Kedo's excellent Mikuni TM34-B65 double pumper flat side kit. All ready to fit, takes stock cables and even supplies adapter to fit the TT600 airbox. Better performance than option 1 or 2, and an easy job. Total cost (assuming Kedo refund the 19% German VAT - which they should being an export order beyond the EU) $900 AUD inc postage. Downside? Not VMX or Vinduro legal and fairly expensive. Otherwise hard to fault this one. 

Option 4 - Keihin FCR-H-39's. I imagine you could get this set up from a few places, but the only shop I've seen it advertised so far is the one I linked above. Probably the ultimate in carb tech and cool for an XT/TT600 engine. Roller slides, good accel pumps and badass looks, etc. Catch is the cost $1,200 USD + postage. Call that $1,650 AUD. Ouch!  Other downside is like option 3, not VMX or Vinduro legal. If I was building an ultimate Motard or Café Racer conversion then yeah baby!

 

Edited by mungus

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Well after speaking to a Yamaha dyno tuner I've gone ahead and bought all the parts needed for a Raptor 660 conversion. He reckons they are a great carb, they do respond very well, despite not being a pumper and that the TK is a waste of time tuning wise. He is about my vintage and has tuned TT/XT and dual carb XR's before, so he knows what they are like. He agrees with me that the TK is a dog, hard to tune well, will never run as well as the Raptor carbs and is a pain for parts. I'll keep my restored TK carbs and all their hardware, for posterity, and in case I ever sell the bike. As it maintains originality and it did start and run with them.  

Total cost to me top buy everything was $610 AUD inc postage. That's about $440 USD and the overseas postage is probably 1/3rd of that bill. It includes a new Motion Pro throttle kit for around $39 USD (with the cable). So for the guys living stateside, figure on $300 USD.

It'll be a few weeks before it all shows up. I'll record the job by photos and write a thread on it soon after. Really looking forward to it. That's all for now... :-)

Edited by mungus
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Looking forward to the outcome of your Raptor conversion. :thumbsup:

You and I are of the same era. Gonna be 52 in about a month and a half. Has to be why we like these '80s bikes so much. And of course the '60s muscle cars.

One other mention. It's not as cool as the '60s stuff but I have a '74 Cougar currently that's a work in progress. Factory 460 car--which is about as "muscle" as you could get at FoMoCo in the mid '70s. The thing actually runs darn well for smog era motor.

 

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Nice. No doubt it would get up and boogie.

Starting to wonder if I've made the right choice going for the Raptor carbs. One extra cost I didn't notice was almost every carb for sale is missing the choke plunger. That adds $60 AUD via eBay (cheapest) and then you have to fabricate a cable of some sort. Probably the easiest way of doing that is buying the cable and modifying it, so that's another $60 AUD. This means my total cost less than $200 less than the ready made TM34-B65 kit from Kedo. And that kit is brand new, looks better, works better (double pumper and ready made choke) and fits up to the stock air box and cables. So I'm buying the Kedo dual TM34-B65 kit, and just reselling my raptor parts on eBay.... Grrrr. To a large degree this issue is geographical. If you live stateside you can buy these parts cheaper than the rest of us, but it still puts the cost up to maybe $400 all up. Then you've gotta figure in your labour and the challenge of getting the raptor manifolds to fit properly etc, vs. a few hundred more for a purpose made, better performing product.

Anyway I guess this is the fun of experimentation! However seeing as how I've already paid for the stuff I may document a trial fit of the Raptor carbs just  for this thread, before fitting the Kedo kit... At least the TT600 community will get some decent photos of the 2 main options, (I don't figure lots of folks want to fork out $1200 for those FCR H 39's... Just saying!).

Edited by mungus

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