17 replies to this topic

[scooterspal]

Hello to all. I recently took delivery on a very decent 1986 TLR 200 and I'm in the process of getting the bike back on the road.

My question at the moment is how you folks have your carburetor adjusted.

I did an ultrasonic cleaning removing most all the parts but the air screw. This has a cap that prevents it from being turned fully out. Currently it seems to be running way too lean and very hot engine-wise. With the seat removed, if I place my hand over some of the air vents it will pick up speed. I assume this means it is starved for gas... but I'm not sure why. I may try and clean the carb a second time and this time remove the air screw.

I should also say this was a California bike originally. The second owner removed most of the emissions stuff and I finished the job last night. I don't think the jetting was any different from a non-California bike but I will have to check this.

Can someone tell me what the jet #'s are for a "normal" TLR200.

Also, why does this carb have two ports for the overflow gas, one on each side, and do you leave the drain tubing connected or remove it?

Edited by scooterspal, 24 June 2010 - 03:53 PM.

[Noggin]

I've just fitted one to my XR and it runs great. Standard jetting is a 98 Main and a 38 Pilot. Needle 2/3 off bottom clip pos.

Get that plug out of Air screw so you can tweak. Only in to satisfy the californian emissions.

Edited by Noggin, 24 June 2010 - 08:09 PM.

[hondanut]

those 2 tubes are not to be covered up, my mate made the mistake of putting some tubing on them and it would not run, the holes are in the bottom of the tube, not in the end, and they are a breather, if you put a tube on them they will no longer breath.
leave them clear.

[scooterspal]

I'm just a bit confused by your replies so let me explain further.

My carb has what appears to be a hose port on each side at the same level and about mid height on the carb. There is a section of hose from each of these ports going down to the single port (which also has a short hose) on the bottom of the carb where all three connect into a plastic joiner. A forth hose leads from here down under the bike frame... a drain like on any other carb.

Therefore, this seems to be a gas drain with three entrances. Is this correct and should this be the way it is?

BTW: There is no clip adjustment for the needle on the TLR200 carb that I can see. It can be shimmed up higher with washers but there is no clip adjustment like on my other carbs. Should it remain where it is?

Edited by scooterspal, 24 June 2010 - 08:34 PM.

[hondanut]

you may not have the same carb then, all of the tlr carbs i have seen has 5 needle clip settings, as most imported into the uk have to be richened up as the japs seem to be riding much higher up in altitude , me and my mate have both had to do this.
the only pipes coming from my carb are the fuel inlet and the one on the bottom to drain the fuel away, the 2 brass projections on my carb are about half way up the slider body section.
i hope this helps

Edited by hondanut, 25 June 2010 - 02:37 PM.

[scooterspal]

I hope you folks can help me get to the bottom of this whole carb issue. Here is a picture of the TLR200 carb that I have right off the Honda parts ordering web site for the USA.

tlr200 carb diagram

It uses a #92 main jet and the slow jet is a #38. On the right you can see the hose setup I'm speaking of. You can also see the needle is fixed with no clip positions.

Now, I will add that Honda makes a carb improver kit #16012-KJ2305 for the TLR200 that comes with a new needle that does have the adjustable clip positions and a new pilot screw set and adjustment screw cap. I have just ordered that kit.

BTW: There is, what they call it here in the states, a rubber snorkel inside the air box to restrict the air flow. Do you have this in the UK and if you do do you leave that in or remove it as some do over here?

Edited by scooterspal, 25 June 2010 - 03:36 PM.

[motofire]

As far as your carb goes...

It seems the hot setup on your bike is to ditch the stock carb for a CRF 70 carb. I have heard of people getting them as cheap as 20$ for Fleabay. If you do a little research you can even find the jetting specs that have been found to work the best.

Lose that snorkel....it ain't helpin ya.

Make yourself familiar with the company I linked below. Great resource and good guys.


http://www.bjracing.com/index.html

Good luck!

[scooterspal]

motofire, on Jun 25 2010, 06:19 PM, said:

It seems the hot setup on your bike is to ditch the stock carb for a CRF 70 carb.

Actually, I have heard of folks using a carb from a Honda CRF100F and jetting the main for 105 and the slow for 40. They are both 22mm carbs. The CRF70/80F is only 20mm I believe.

In fact, I did purchase a 2007 version on Ebay to try this but the catch is the throttle cable. The two slider caps are not compatible and the cable for the CRF100F is too short to work on the TLR200. Asking around I cannot get an answer as to how they made this work.

Seems this is more of an urban myth

For now I'm going with the stock TLR200 carb and some tweaking. The bike ran for 4500 miles with it so it must have worked well enough at some point.

Thanks for the tip about bjracing!

Edited by scooterspal, 25 June 2010 - 06:40 PM.

[motofire]

Your right it is the CRF100.

The cable problem....change out the stock throttle and have a custom made one done by BJ Racing.

I'm in the middle of doing mine over.

Body from BJ Racing
Hand Decomp Lever
Domino Throttle
Wes Exhaust

Waiting for....I'm rebuilding the motor this winter. Falcon shocks. Crf carb. New Gearing....and if I'm lucky, maybe a BJ Racing cylinder/head.

Good luck to you.

[scooterspal]

motofire, on Jun 25 2010, 08:04 PM, said:

Your right it is the CRF100. The cable problem....change out the stock throttle and have a custom made one done by BJ Racing.

Hey Moto:

It's not the throttle end that's the problem. The threaded metal cap that fits atop the carb slider shaft is smaller on the CRF100F. The end of the cable shroud is somehow press fitted into the cap. It is loose enough so that it can rotate around but it will not pull free of the cap.

I can probably Dremel cut a notch into the top of the cap and widened it (with a screwdriver) so that the shroud pops free. That way I can use the OEM cable with the CRF100F carb.

The OEM throttle cable is way thinner so that it can run under the fuel tank along the frame rail. The return spring is also way stronger in the OEM carb. Not sure if it will fit the CRF carb but it just might.

BTW: If you don't mind... why go with the manual decomp system. I've heard that anyone who has tried it went back to the automatic. What do you gain this way?

Edited by scooterspal, 25 June 2010 - 08:26 PM.

[mcman56]

The original Reflex carb can work fine.
1. The two ports on the side that connect to tubing are vents to the float bowl. As gas gets lifted into the carb, some air needs to go in. These need to vent to atmosphere.
2. An adjustable needle from a 70s street model 125 or a TL125 will fit. In fact, the Reflex carb is pretty much the same as a TL125 carb. They used to sell after market carb rebuild kits on ebay for XL or SL 125s. These came with the needle and that is where I got mine. Will the needle from your XR70 fit? Is it a similar length? You could try it. Shimming the original needle should also work.
3. A 100 or 105 main jet should be about right. These jets are the same as the 1990 XR100 and probably other years.
4. You can pull the cap off to adjust the idle mixture.
5. The pilot jet is different than most so is a bit more difficult. The original 38 was available from Honda but nothing else. It needs to be slightly larger to avoid the cough and die symptom. You can buy a tiny, #60 thru #80, drill bit set from a place like McMaster Carr and go one size larger than it is already. That is what I did.
6. You can remove the snorkle but I never did a comparison to see if it really helps.
7. You can even bore the carb out to the equivalent of a 24mm. It is a bit of work but can give a nice boost in top end power. If you look at the end of the carb that bolts to the engine, you see an oval shape that is non symmetric and oriented towards the bottom. This can be opened so the oval is symmetric top to bottom. The top of the oval does not become active until the throttle is opened so there is no affect on low speed operation.

[motofire]

scooterspal, on Jun 25 2010, 04:23 PM, said:

Hey Moto:


BTW: If you don't mind... why go with the manual decomp system. I've heard that anyone who has tried it went back to the automatic. What do you gain this way?

The auto decomp can cause the inner ratchet to break on the kicker. Which is an, already weak and hard to find part. Also you can use the kicker from an XR200, though their may be some mods you have to do.

One other good mod is to get rid of the linkage on the shifter and go direct to the shaft.

Doing these mods and cutting off the extra tabs on the frame and losing the lights can save you some #'s. If you don't care about the weight, no worries.

[scooterspal]

mcman56, on Jun 26 2010, 05:50 AM, said:

The original Reflex carb can work fine.
1. The two ports on the side that connect to tubing are vents to the float bowl. As gas gets lifted into the carb, some air needs to go in. These need to vent to atmosphere.

So are you saying to remove those two hoses that run to the bottom port?

What about the one at the bottom. Should that remain connected to the hose drain?

... and thanks for your very detailed reply. I'd like to go with the OEM carb at least for this season so I can get this bike on the road quickly. Here in Connecticut we have such a short one.

Edited by scooterspal, 28 June 2010 - 01:12 PM.

[scooterspal]

motofire, on Jun 26 2010, 03:10 PM, said:

One other good mod is to get rid of the linkage on the shifter and go direct to the shaft.

This is one mod I'd like to make. If you have any details on how please let me know.

[hondanut]

just remove the gear lever, and put it direct onto the shaft out of the gear box, (after removing the linkage), the shaft size is the same, so it should go straight on.