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Discussion Starter #1
Done with the stock carbs..... I have a 1987 T Dub with constant carb issues....Nothing new here....
I have 2 rebuilt stock carbs / sonic cleaned / oem rebuild kits ...
Still hate the damn things... Poor response , cold blooded , throttle surging junk ...
I opted for the $24 Ebay BW carb , 1/4 turn roller throttle and a new pair of switches all for $45.02 . Less than 1 rebuild kit for the stocker....

I'll let you know how it all works out....
 

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I did the mod. Works really well. I also got a replacement intake boot and plan on using the old one as a spacer.
That's a good idea. I got one of the "cheap" carbs when I was having problems with the stock carb. Eventually, I got the stock carb working, so no need for the change. However, now that I have a new TW, I may very well try the "cheap" carb when I rebuild my old TW engine. Your post may prove to be a good/better solution than what I was dreaming up! Thanks
 

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Discussion Starter #5 (Edited)
The carb showed up a few days back and the throttle came yesterday , thought I'd better update this thread.
The Carb is a standard China BW replacement available from many vendors on ebay.
I have run this same carb on many vintage resto mods with good results...

CARB_040_01.JPG

I opted for a 1/4 turn roller throttle ( again from Ebay ) I like 1/4 turns , they fit my riding style well.

$_12.JPG

The throttle came with a 40" cable that unfortunately had to short of throw for the carb.
Not a huge issue if one has a dremel tool .
The carb requires 3" of throw to operate correctly . I simply trimmed 1" of sleeve ( careful not to abrade the cable )

1015141172 (4).jpg
1015141175 (3).jpg

The other problem I ran into was on the carb cap itself.
The carb comes with what is called a noodle cable adapter, I required a short threaded adjuster.
Thanks to my many years of hording parts I replaced the cap with one from a 28mm Mick that I had in the bins.

1015141174 (3).jpg

I now have a bench tested carb and throttle ready for the bike.
I will be installing the new system once the new switches show up.

As I can only add 5 pics to each post , I will have to add the switches to a new post..... Sorrrrrrrry.... Gregg
 

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Discussion Starter #7
While waiting for the switches to cross the sea.
I went ahead and installed the throttle and carb yesterday.
The installation is a straight forward affair .
As mentioned by others the carb is about 1/2" narrower than the stock unit so an extension will have to be made for the air box boot.
I opted for " Gorilla Tape " as a temporary solution.
I will address this issue properly this fall when the bike will be torn down yet again for a frame color change.
The 40" throttle cable is just barely long enough . I recommend buying a 42 - 44" cable .

The ride:
No surprise here....
Huge difference.....
Much better idle control. The engine will now hold a consistent 600 rpm idle without stumbling.
No hesitation when accelerating off idle .
No flat spots.
Best of all is the acceleration through out the full range of the engine.
The engine pulls much harder on the bottom , responds quicker and is snappy .
Part of this is the 1/4 turn throttle , but the majority of the performance gains are caused by the new carb.
Don't be put off by the fact that this carb is an inexpensive Chinese copy of a Mikuni VM spigot mount carb. ( one of the best carbs ever offer'd by Mikuni ).
It is a far better carb than the stock TW carburetor as it doesn't suffer the compromises that the TW's does to be smog and DOT compliant.
This carb was just designed to perform , and perform it does....
The unit I order'd was jetted to be a direct replacement for the Yamaha BW.
Seems the Chinese were pretty accurate in there set up. After a 20 mile ride on a cloudy day here in Astoria ( mostly at sea level ) the plug has a nice chocolate sheen.
None of this is new data.
Many TW riders and owners have done this conversion before me with good results. I'm just fallowing there lead......
If you are contemplating a carb replacement or rebuild for your TW in the future, I highly recommend this alternative to the $45 rebuild kit or the $245 -$300 stock carb.
Happy trails.... Gregg
 

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I wish someone would take some pictures, step by step. We need to know how the carb and cables hook up. What do you have to do? 40 or 42 inch new cable? Ok. Would it be better just to go to the 42 or even 44 if you have risers or high taper bars? Old carbs and new carbs are different. One connects on the right, one connects on the left. We need both solutions, and pictures of both. Thanks :)
 

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Discussion Starter #9
Old and new will be the same as the intake is fairly center'd.
The new carb cable feeds through the top of the carb.
The carb cable is a direct mount through the cap to the slide , unlike the stock cable which is linkage mounted to one side or the other.
I'd run a 42" with stock risers and bars ,44" for taller risers or full taper wide bars.
I will add pics of the full process once the switches arrive as I will be tearing everything back down at that time.
Sorry for the lack of forethought.
I'v done this sort of thing so many times , I just take for granted that people understand the difference between a slide mount and a linkage mount carb.
My bad .... Seriously , MY BAD. I will remedy this.

Happy trails...
 

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Old and new will be the same as the intake is fairly center'd.
The new carb cable feeds through the top of the carb.
The carb cable is a direct mount through the cap to the slide , unlike the stock cable which is linkage mounted to one side or the other.
I'd run a 42" with stock risers and bars ,44" for taller risers or full taper wide bars.
I will add pics of the full process once the switches arrive as I will be tearing everything back down at that time.
Sorry for the lack of forethought.
I'v done this sort of thing so many times , I just take for granted that people understand the difference between a slide mount and a linkage mount carb.
My bad .... Seriously , MY BAD. I will remedy this.

Happy trails...
Thanks Boxcar. I know it has interested a boatload of people. But without knowing how, I and probably others would be hesitant to try it. Thanks so much Bro!!
 

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Thanks for the pics and the details Gregg. If you are in Astoria, I'm right across the river in Grays River and am interested in this mod.
 

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I applaud you and the others on this forum for investigating, and doing this mod. I have an '87 and a '99 model, and don't have so much trouble with them. I do, however, have starting issues occasionally, soooooo, I read this with interest.
 

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Too many clone carbs to choose from. If it says it is a BW replacement, I should be good to go right? There is a 24, 26 and 30 mm VM available.
 

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Okay. Got my ISO carb from ebay for $28. Installed it and low and behold it fired up. I plugged the little spiggot on the air intake side with some glue and .22 shell. The brass looks slick. I bought an aftermarket throttle and cut off the bent neck on the top of the carb with my dremmel. I have it gaffer taped to the throttle cable for now. Duct tape bridges the gap between the airbox and the carb. (It ran fine without it.) Now that I'm all hooked up -- it won't start AND gave a couple backfires. Hmmmmmm. Could the throttle linkage be too tight? That's the only thing I can think of. That changed. I didn't even take the carb off the bike -- just pulled the top and installed the throttle cable.

Yup -- too tight. I'll have to pull the cable and modify it again. I tried everything and nothing would get it to budge -- then I pulled the cable off the throttle and it fired up.

Meanwhile, new battery, new plug, new oil and filter (PO had no oil screen or spring in there, so that is on order) and I adjusted the valves (first time ever doing that.)

I also noticed that it starts and runs without the choke - but I don't have it hooked up to the airbox just yet.
 
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