TW200 Forum banner

1 - 20 of 24 Posts

·
Registered
Joined
·
93 Posts
Discussion Starter #1
I have a TW '93 carb I'm planning on refurbishing soon and I was wondering whether I should opt for the rebuild kits on Amazon/eBay or whether I should stick with OEM parts?

Some have said on the forum that they stick with OEM jets because they are guaranteed to be consistent, but does anyone else feel strongly one way or the other about all the other parts?

One of my carbs appears to have sat in a previous owner's ethanol gas for a long time so it's pretty gross looking inside. I'm going to have to replace or thoroughly clean everything on that one.
 

·
Registered
Joined
·
93 Posts
Discussion Starter #3
Unless you really want to keep it original, I have heard the $40 ebay/Amazon carbs work pretty good. No mess. Bolt on and ride.
In this case I want to fix it myself so I learn how they work. I'd really like to be able to tune them properly too.

Sent from my ONEPLUS A6013 using Tapatalk
 

·
Registered
Joined
·
8,371 Posts
I always buy OEM original carb parts because the kits I tried were pure garbage. Some do say the kits from Pro Cycle are pretty good however. On another note, chances are good that you don't need new jets as long as the old ones have not corroded and are not clogged. What I always replace is the float valve and seat because there is a fine mesh screen under it that tends to be severely clogged every time I get one out. Pay very strict attention to the directional arrow on the bottom of one of the float pin posts. That is the direction to push the pin out and even then you must be super careful to not break the post.

GaryL
 

·
Registered
Joined
·
1,482 Posts
Thin metal guitar strings are good for getting small holes and passages unclogged. My neighbor gives me all the strings he breaks.
 

·
Registered
Joined
·
8,371 Posts
Some years back while involved with non MC projects I bought a set of tiny Micro carbide drill bits. I find these come in super handy when working inside carbs. Numerous times I have bought new jets while rebuilding my carbs and I always find the exact fit drill that I can push through the hole snug but easy and with no drill attached. Once I find the bit that fits the new jet I try it in the old jet and only once in all my carb rebuilds did I find the old jet worn or oversized. It came from a very cruddy carb and I had to run the old jets through the ultrasonic cleaner a bunch of times. IMO, not much goes bad with the jets as long as they don't sit in corrosion for a long time. Fuel pushing through them does not necessarily open them to a larger diameter as we might think. I figure if the drill fits snug through the new jet and also through the old jet then there is no reason to replace the old one.



GaryL
203561
 

·
Registered
Joined
·
1,928 Posts
I've always found that you can't go wrong with OEM parts and try to keep my bikes and their innards the same. As far as jets go unless you are trying out different sizes there is almost never a need to ever buy a new one. They do get clogged but whether you used a gauge/pin kit very carefully or ultrasonic cleaning (or both) they don't really ever wear out. They can be easily damaged if you put/push something in that is too big though. Very soft metals.

I just opened up and cleaned the carb on my XR250L, was having a hell of a hard time kicking it over though once it started it ran fine. This is what I found:
IMG_1137.jpg


YIKES! Darn The Pine Barrens! Other than the hard starting it ran fine, pretty amazing! Go Honda.
IMG_1139.jpg


All better after Ultrasonic cleaning (water and Simple Green) and double cleaning the jets with small strands of wire:
IMG_1180.jpg

I order a lot of Japanese parts from Babbitt's On-Line. My carb gasket re-build kit came today, all Honda OEM. Some of the Chineese stuff is cheaper $$ but It always seems to be "off" in either the material used or actual quality of the cuts. Keep in mind these are parts for a 30 year old dirt bike so kinda vintage, gotta keep it original.

However I have thrown complete Chinese Carbs on a bike or two and they worked fine, go figure. I just wouldn't mix aftermarket parts just because they are cheaper into something already OEM.
IMG_1137.jpg IMG_1139.jpg IMG_1180.jpg IMG_1176.jpg
 

·
Registered
Joined
·
93 Posts
Discussion Starter #8
That's a lot of great advice. And it looks like I now have a good excuse to buy one of those harbor freight ultra sonic cleaners I've been looking at for years!

One question on the simple green though: do you use the regular simple green or the mil-spec simple green? I've heard the regular stuff doesn't react well with aluminum but that's all I've ever used. And does it really matter on a bike?

Hopefully, I'll get my parts this next week and start the rebuild process soon.

Sent from my ONEPLUS A6013 using Tapatalk
 

·
Registered
Joined
·
8,371 Posts
In the ultrasonic from HF I use the regular Simple Green and actually have better results using Pine Sol, both from Sams club. HF sells a small and a larger Ultrasonic cleaner. The little one works great for the small parts and the large one fits the entire carb body and has a heat setting. Go big or go home!

GaryL
 

·
Registered
Joined
·
93 Posts
Discussion Starter #10
In the ultrasonic from HF I use the regular Simple Green and actually have better results using Pine Sol, both from Sams club. HF sells a small and a larger Ultrasonic cleaner. The little one works great for the small parts and the large one fits the entire carb body and has a heat setting. Go big or go home!

GaryL
It looks like I'm going BIG. Harbor Freight only lists the big unit on their website now. That means they probably don't even have the little unit any more in their stores, but I'll check to be sure.

Thanks for your help.

-Sam
 

·
Registered
Joined
·
9 Posts
After working for a Yamaha dealer for 30 years (and I love the tw200!) Yamaha carb parts are horribly expensive. We didn't use aftermarket parts at the dealership, but many of my friends did and had good service from them. Would I try them on my own bike, absolutely.
 

·
Registered
Joined
·
93 Posts
Discussion Starter #12
After working for a Yamaha dealer for 30 years (and I love the tw200!) Yamaha carb parts are horribly expensive. We didn't use aftermarket parts at the dealership, but many of my friends did and had good service from them. Would I try them on my own bike, absolutely.
Thanks for that insight. I'm pretty price conscious so I think what I'll do is buy the aftermarket rebuild kit and see how much of it I have to use inside the carb. On stuff like this I usually buy the more expensive eBay options. They usually come from American sellers who care a bit more about quality than the cheapest Asian stores.

And based upon the observations from GaryL and stagewex it doesn't look like I'll need to replace the jets if I clean them carefully. I may break down and buy one of those micro carbide drill sets too because I can see how useful they would be. They are only $11 shipped from AliExpress and they might even come with a free coronavirus sample during this time of year!
 

·
Registered
Joined
·
19,816 Posts
Like Harley-Davidson and most other respected brand names Yamaha is more of a product assembler than a manufacturer these days. Rather than Yamaha casting their own jets some jobber manufactures them and feeds them into the supply stream. Yamaha purchases some of them, then the usually asian manufacturer attempts to vend remainder through any source available. Of course other competing manufacturers jump into the market ,copy and vend essentially the same part with minor variations in quality. So buying directly from a Yamaha dealership guarantees an OEM price, but not necessarily identifies the actual manufacturer nor guarantees the quality...remember the 2 vs 4 hole TW oil filters that the dealerships would inadvertently sell? Think they were actually fabricated in a plant owned & operated by the Yamaha Motor Company? Sometimes winning the lowest bid comes at expense of quality control.
 

·
Registered
Joined
·
2,418 Posts
Like Fred says, no guarantee where the OEM parts are from.

Carb builder Teikei has a factory in Japan, but a few years ago, in conjunction with Yamaha, Teikei built a factory in China.
I suspect this is where all the "clone" TK carbs that are on Ebay/Amazon are coming from.
I have had several of the clone carbs, and the machining quality is very good.

jb
 

·
Registered
Joined
·
2,418 Posts
I see the edit button hasn't been fixed yet........ahhhh! I found the edit button...:giggle:

Here are some of the companies that a large Chinese company makes parts for (and in some cases complete vehicles):





jb
 

·
Registered
Joined
·
93 Posts
Discussion Starter #16
Of course other competing manufacturers jump into the market ,copy and vend essentially the same part with minor variations in quality. So buying directly from a Yamaha dealership guarantees an OEM price, but not necessarily identifies the actual manufacturer nor guarantees the quality...remember the 2 vs 4 hole TW oil filters that the dealerships would inadvertently sell? Think they were actually fabricated in a plant owned & operated by the Yamaha Motor Company? Sometimes winning the lowest bid comes at expense of quality control.
One of the things that has become a real problem recently is that the US Government doesn't enforce its own laws concerning the proper labeling of products. Amazon and eBay are full of products that have no 'place of origin' stickers , FCC stickers, or even electrical spec stickers. Once I bought some electronic stuff that didn't come with power bricks but it was impossible to tell what kind of power the device actually needed. I took an educated guess and got lucky, but it can be a real problem.

I wish the eBay and Amazon vendors were better with their product descriptions. Then it would be a whole lot easier to distinguish between the quality products and the cheap knockoffs. This is especially true with a lot of the aftermarket TW parts.
 

·
Registered
Joined
·
93 Posts
Discussion Starter #17
After reviewing all the awesome feedback to my first question I decided to go cheap(er) and bought an aftermarket carb rebuild kit. I bought what I thought was a high quality generic one off of eBay but I actually got an allballsracing.com kit. I paid $35 for it and it came with everything including needle shims so I could give it a little extra oomph (I was lazy and didn't want to source them separately. I live a long ways from a hardware store.) Also, I opted to save some money and hold off on the ultrasonic cleaner and just use a can of carb cleaner for my first foray into the mysterious innards of a carb.

My results were mixed. For the most part the aftermarket parts fit but there were a few exceptions.

When I pulled the carb slide and removed the needle, I noticed that it had a little lacquer on it that came off pretty easily. Just for fun I tried to use the new needle instead, but it wouldn't slip all the way inside the little indexed washer plate that holds it in the slide. My micrometer said it was a perfect match when I measured it so I knew I was using the tool wrong!

What I discovered was that the OEM needle had the sizing stamp on the top end of the needle and the aftermarket needle had the sizing marks about a 1/4 inch down from the end. So when the number stamp impressed the needle, the metal was pushed out of the stamping marks and increased the diameter of the needle at that point. I could've just sanded that off, but I opted to use the old needle instead.

Also, as I examined the OEM jet (114) and compared it to the aftermarket jet (another 114) I noticed that the aftermarket jet did look bigger. That could've been caused by buildup on the OEM jet, but I don't think so. I soaked it in carb cleaner, gently poked a wire end in there and it never got bigger. So I opted to stick the original jet back in the carb too.

Now, what was really cool about the aftermarket kit was that the mixture screw (I think I identified it correctly) came with a knurled knob extension on it so it would be a lot easier to adjust once it's on the bike. Unfortunately, the spring that came with it seemed like to had more wire than the OEM one. I just couldn't get the OEM one to catch the first threads with the aftermarket spring in the hole although I didn't try to force it. So I used the old OEM spring. In addition, the aftermarket o-ring that came with the knurled one was way too small. I had to dig up a replacement from my o-ring box. It was the right size but I'm not sure whether a standard water-rated rubber o-ring is rated is good enough for fuel or whether I really need something special.

Interestingly, I tried using the old mixture screw but I couldn't get it back in the hole. A previous owner had cut off the cap covering the screw so he could do adjustments, but once I removed it, it didn't want to go back in. The OEM o-ring wouldn't fit back in the hole even after I reamed out the hole a bit. It was tough even with the aftermarket pilot jet but a little silicone spray helped me get it in.

I really wish I had sprung for the ultrasonic cleaner. I can see how spending $80 bucks on a tool like that can make everything much easier. As it was, I spent a lot of time gently cleaning everything by hand. A cleaner is definitely going on my wish list.

If I had to do it all again, I think I'd just open the carb up and see what could be cleaned first, then source whatever replacement parts I needed. All the aftermarket gaskets, screws, shims, filter thingy, tank inlet needle doodad, etc. were spot on. But some of the other stuff was hit or miss.

This experience was certainly a lot of fun. I've never opened up a carb before and now I have a better appreciation for the brilliance of the engineers who invented these contraptions. There's a lot going on in those little pot metal boxes!

-Sam

IMG_20200223_164424.jpg IMG_20200223_165444.jpg IMG_20200223_173157.jpg IMG_20200223_142704.jpg IMG_20200223_150344.jpg IMG_20200223_150913.jpg IMG_20200223_154235.jpg
 

·
Registered
Joined
·
9 Posts
Sounds like you did a good job. I have found occasionally mixing new/old parts has been necessary also. The O ring issuse you had is common, they want to swell when taken out are are difficult to get back in. Oh and your 'replacement' O ring is probably fine, as I remember, that adjustment screw is an air screw for mix at idle and not a 'fuel' mix screw. Set it between 3/4 and 1 1/2 turns out. Wherever it seems to idle the best. We didn't use an ultrasonic at the dealership, but heated a pan of cleaner on an elect hotplate to make it more aggressive and left the carb submerged for the day. Shut it off when we left, then put it all back together the next day. You're doing great, having fun, and learning how it all works.
 

·
Registered
Joined
·
45 Posts
I think it depends on the carbs and kits.
I work on a lot of Seadoo’s and Yamaha wave runners and every one of the aftermarket carb kits are junk and cause running issues and engine seizures. For those carbs you have to use only Genuine Mikuni carb parts.

The old TW isn’t that picky.
 

·
Registered
Joined
·
93 Posts
Discussion Starter #20
Sounds like you did a good job. I have found occasionally mixing new/old parts has been necessary also. The O ring issuse you had is common, they want to swell when taken out are are difficult to get back in. Oh and your 'replacement' O ring is probably fine, as I remember, that adjustment screw is an air screw for mix at idle and not a 'fuel' mix screw. Set it between 3/4 and 1 1/2 turns out. Wherever it seems to idle the best. We didn't use an ultrasonic at the dealership, but heated a pan of cleaner on an elect hotplate to make it more aggressive and left the carb submerged for the day. Shut it off when we left, then put it all back together the next day. You're doing great, having fun, and learning how it all works.
It was somewhat satisfying to install the carb on the bike and have it start up right away. I actually didn't think that would happen!
 
1 - 20 of 24 Posts
Top