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Discussion Starter #1
Hello, everyone i just joined so here is what i have. It's a 1994 i bought 6 years ago. It's not as colorfull as the mint 1994 i had 15 years ago. So it has some different plastic parts, painted gas tank, and new seat cover, ran just fine but not too pretty. The problem is the gas was not drained and it sat for 2 years. I removed the tank thoroughly cleaned it. When i inspected the fuel " petcock" that i removed for cleaning it turned really hard. I knew something was wrong, sure enough the gasket was shot.
I got the whole unit new for less than $ 15.00 from amazon. I'll buy the rebuild kit for the old one this winter and keep it for a spare.
Now the carb ! Its a mess ! I've got it soaking but it'll take a while. I'm going to buy a new carb and rebuild the old one this winter when i have time. My question is should i buy a totally stock one or is there a better alternative ? Sure i'd like more horsepower, Higher speeds, but will reliability / engine life suffer. And how much would i really gain over stock ? On Youtube the Hookstown Hooligans put a YZ 80 carb on a TW but that was a 2002 and had the new "constant velocity" carb. I already have a "direct pull" type. I also need new "sneakers" Tires ! The Shinko looks like the best for the front ! ? And i guess the stock Bridgestone is the only dual purpose tire available for the rear ! ?

I sure would appreciate any and all advice / knowledge you folks have for me.
Thank you in advance.
Best regards, John P. Hedlund
 

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First the easy answer – the rear tire. Yes, the stock TW34 rear is the best dual purpose.

Next up is the carb. Unless you go for a slide pumper, ($450), the stock slide is your best bet (IMO). The pumper can reduce flat spots, but unless your drag racing the thing, it’s largely irrelevant

You’ll likely get several recommendations for Chinese carbs, all of which are cheap as chips, and take you off into the woods as far as jetting advice goes. They’re all slightly different, change every six months, and untraceable

My honest advice is take your original carb and throw it at a shop to sort out. The cost will not be much more than fitting a Chinese jobby on the bike (carb, rubbers, cables, jets et al), and we can always help out on the original carbs because they are a known quantity …….
 

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Discussion Starter #3
Thank you Purple.
That's what i thought for the carb. Back in the day i could disassemble a Rochester quadrajet 4 barrel rebuild it on the flatbed and have it back in and running in a couple hours. So just wondering how complicated the TW carb is ? Are there special tools, or adjustments the backyard mechanic can't do ?
Also, what front tire is recommended for on/off road besides the "deathwing" ? the 130/80/18 Shinko looks good for the front. I'll be riding the local streets and dirt roads / woods. I see a lot more selections for rubber if you only ride street.
Thank y'all very much.
John.
 

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For when you rebuild the old carb (if it might help)...



...and re: alternate carbs...


...and if you're specifically interested in a Mikuni VM26...


Hopefully some of that light reading will help. I had those handy b/c my 1994 is a little starved for fuel (or so I suspect) and I intend to pull the petcock and carb later this fall and rebuild/replace whatever is necessary to get it working properly.

Enjoy.
 

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Discussion Starter #5
First the easy answer – the rear tire. Yes, the stock TW34 rear is the best dual purpose.

Next up is the carb. Unless you go for a slide pumper, ($450), the stock slide is your best bet (IMO). The pumper can reduce flat spots, but unless your drag racing the thing, it’s largely irrelevant

You’ll likely get several recommendations for Chinese carbs, all of which are cheap as chips, and take you off into the woods as far as jetting advice goes. They’re all slightly different, change every six months, and untraceable

My honest advice is take your original carb and throw it at a shop to sort out. The cost will not be much more than fitting a Chinese jobby on the bike (carb, rubbers, cables, jets et al), and we can always help out on the original carbs because they are a known quantity …….
For when you rebuild the old carb (if it might help)...

...and re: alternate carbs...

...and if you're specifically interested in a Mikuni VM26...

Hopefully some of that light reading will help. I had those handy b/c my 1994 is a little starved for fuel (or so I suspect) and I intend to pull the petcock and carb later this fall and rebuild/replace whatever is necessary to get it working properly.

Enjoy.
Yes ! Great reading on the subject !
Thank you.
 

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The old Q-jet......I have done a few of those myself. If you can do a Q-jet you can do a TW carb no problem.

The intake port on the TW head is 30mm. If you get a 30mm aftermarket carb you will notice an increase in power and acceleration. The stock TW carb is <30mm. With an aftermarket carb. you will have to cobble things together. No big deal. Not that hard or expensive.

Here is a comparison of the stock (left) and a 30mm aftermarket carb.(right). You can easily see the size difference. Right now gammer73 and I are both experimenting with the carb on the right. Reports to follow.
P1200072.JPG
 

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Discussion Starter #7
Thank you elime. Something to consider ! I'll drive mostly street when i'm in Norfolk Va. but i spend my summers in the mountains of Oquossoc, Maine, where it's more dirt roads and logging roads 10,000 - 15,000 ft. ! so 2 carbs....... ? One set up for sea level, and one for the elevation ! ? Hmmmmm... Swapping them out isn't 10-15 mins. ? And i don't have to monkey with them once they're set up ! In theory !!!!!!!!! Ha Ha....

johnpeer
 

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Discussion Starter #8
Thank you G-FOURce for the Forum leads on the carb. ! I'll be soaking up all that knowledge this evening !!!!
johnpeer.
 

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johnpeer do you mean 1000-1500ft elevation.? i think katahdin is only around 5200ft.
Pretty sure he did, Nitro. The highest elevation along the entire AT is in NC at Mt Mitchell (~6.5k ft) with the northern terminus being right there at Katahdin.
 

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Discussion Starter #12
Mea culpa ! My bad. No i'm not planning on riding it to the top of Everest LOL. Meant 1,500' - 5,000'. 4 years ago i rode some trails to the top of Saddleback Mtn. 4,000' and it ran like crap. The lakes here are 1,500' everything around is higher, but i'll be spending half my time in Norfolk Va. at sea level. Would it be worth my time to have 2 carbs set for the different altitudes ? Also if i want a new stock carb which one ? hard to tell what one is stock dozens of them for sale. Same with the rebuild kit dozens of them for sale. I'd like to get what has been tried and proven by the people who work on, and ride the TW, not what a salesperson is pushing. I saw one for $34.99 and one for $369.00. Or should i get one from a Yamaha dealer ? Very confusing !!!!!!
Thanks to the help here i should be able to figure it all out soon.
If you had to buy a new stock carb which one ?
If you had to buy a rebuild kit for a stock carb which one ?
Thank you all for your help ! Excellent place to learn about my TW.
John.
 

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Clean your stock carb really well. Blow out the passages with compressed air. Get a new #112 high speed jet (second choice is a new #114 high speed jet) and a new #40 pilot jet. I have done this on two TW's and they run well from sea level to about 4500', which is as high as I have had them. I am sure they will do well above that but I haven't taken them higher.

If those jets in your carb are older than 5 to 8 years they need to be replaced. No matter how good they look replace them.
 
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