If you feel like you have a deja-moo, well go back quite a few pages. Now I agree with all of you, who think that flatslides are the way forward, but on my Everyday TR1 practicality has its place too. And as I had to do an install from scratch, I thought I might as well document it.
You need:
- two VM38-9 carbs,
- two VM38-200 inlet rubbers,
- two 90 degree silicone reducer bends 57 and 64mm on their respective ends (that is if you want to suck through the frame and stock airbox like me),
- a 2in1 throttle cable for VM36/38 available from various XS650 shops (#51-6506),
- choke-knobs as fitted to TM38s (not strictly necessary, but makes it easier to pull them out),
- two 40 degree throttle cable adjusters and
- four (4) M5x16 allen head bolts and spring washers per carb for a total of eight (8).
The latter not being strictly necessary, but it's a lot nicer to have some nice hardware on your carbs. The stock philipps bolts are actually JIS-heads, which means it's very hard to get screwdrivers in Europe that have the correct angle and not tend to slip out.
Optional:
- you can also get a softer throttle spring (VM34/55),
- longer straight throttle adjusters (VM30/77) and
- a Mikuni Hex-mainjet jet tool if you think, you will have to change jets often, get . (This will allow you to swap mainjets with the carbs installed.)
- The lower half of an Yamaha XS or SR left handle-bar switch, if you want to remove the choke lever in the most clean way possible. One can also just simply unbolt it.
Take the float chamber off and swap mains and pilots for the sizes of choice (in my case 17.5 and 175). Add a bit of copper-slip or other anti-seize of choice to the new bolts (after you put on the spring washers) and reinstall the float chamber.
Swap out the lever choke (the lever is on the wrong side) for the knobs.
Yes, the TM38 chokes are a bit too long and will not go down all the way. Installation may also be easier with the knob pulled upwards.
Now the next step is, where things get a bit tricky. In the past, these 40 degree bends resulted in the perfect slack in the throttle cable, but either the cable has been shortened by me before (quite possible as it wasn't in the original bag) or these are slightly longer, either way they ended up being too short by a few mm. The stock (short) straight adjusters do work, but leave little room for adjustments, so there's longer (straight) ones available with Mikuni part-no. VM30/77.
On the subject of how to get it all back together, i.e. how to install the spring and hook the cable into the slide, that's how I do it.
And then finally install the lot. As you can see, the 40 degree bend would be nicer as it routes cable in a wider bend, decreasing the forces substantially as it avoids that last kink. Now if I absolutely wanted to make it happen, shortening the sleeve of the single cable by 20mm or so should give me ample room for adjustments, probably even 10mm being more than sufficient.
Now being a stubborn b*st*rd has its merrits, especially if if ends in "I-want-those-40-degree-bends-and-even-if-it-kills-me". If you leave out the locknut, the cables are just long enough then.
With that sorted, my old parts stash was raided for a suitable lefthand switch cluster lower, which comes without the choke lever. As they absolutely identical, it's just a case of not losing any bolts and swapping bits over.
The original TR1 lower.
And then the last bit was to properly sync the carbs both at idle and at midrange.
So that's taken me longer to write down than to install, which was
roughly 45 minutes to one hour all in all. Does it require a sync? Well
thanks for asking, but if you check the cable lengths of the twin cables
and they are the same, all you have to do is set the adjusters on the
carb tops to the same height and that'll be good enough for a first
start. Mine idled a bit higher than I like and the airscrew was out a bit too far, but
after filling the float bowls up with some fuel, she fired right up.
As I had to revisited this post anyway let me recommend some further reading from this blog, some of which I wrote much later:
You can use stock intake boots and frame to carb elbows?
ReplyDeleteNo, you VM38-200 inlet rubbers and the carb elbows come from a turbo shop and are 90 degree reducers. I think 54mm (or 57?) on the frame and 63mm on the carb.
DeleteThanks, this post helps me a lot.
ReplyDeleteDidn't the idle speed screws of the carbs hit each other when the carbs are installed?
No, the idle-speed adjusters are on the outside. You can see it below the pink breather tube in one of the pictures above.
Delete