adjusting new throttle cable on 38mm pwk airstriker

[Rollscanardly]

ok this may be a stupid question but i have an inch or better of play in my thumb throttle and i cannot adjust it out...When i got the carb it had no cable, so i bought one from magic racing, the carb came with a cap that had a little connector with a nut, and on the cable i ordered there was the same connector and nut, i only used one of these connectors, is this correct? Is cable routing a possible reason for the slack? any input on this would be great thx in advance
Hunter

[wilkin250r]

Do you know the history on your throttle and cable?

Often people put 400EX thumb throttles on if their old throttle breaks, because the 400EX throttle is much easier to find. It will work, but not as well. It often has a lot of slack, and it also has a shorter throw, so it doesn't open the carb all the way.

That's ONE possibility.

[Rollscanardly]

this is a good possibibility, since the inside of the thumb throttle appears to be altered....is this dangerous to use?

Thx a ton fo the reply...also will this cause my R not to idle properly?

Thx Hunter

[wilkin250r]

It's probably not dangerous. The only issue I could possibly see is all that slack could cause the cable to get hung up or bind up somewhere it's not supposed to.

As for the idle, no. If your quad won't idle, you've got a problem somewhere else.

Now, many people use their adjustments to hold the slide open a little for the idle. It's a band-aid fix, it doesn't fix the REAL problem, but it's effective and safe. If/When you get your cable fixed, you could use the same band-aid fix.

[deathman53]

get the cable for a 85 atc250r, its different than 86-89 atc/trx 250r's. It fits pefect. I did this on my friends.

[mineralgrey01gt]

since it was brought up, is running a 400ex thumb throttle not a good thing to do? I have one I plan on runnin on my 250r and if its not gonna open the carb up all the way then im getting rid of it lol

[86250rrider]

honda part # 17910-964-000. this is the one i use with a thumb with a 38mm a/s and it works perfectly. hope this helped.:D

[wilkin250r]

Motion-Pro also makes a cable specifically for use on the 250r with a PWK carb. It has extra adjustment in the middle, so you COULD use it with the 400EX throttle and take out all that slack.

I'm pretty sure the carb still won't open all the way with the 400EX throttle, even with all the slack taken out, but it will open 95%, and function just fine otherwise. I did this for a while until I could locate a stock thumb throttle that was up to my standards.

Most dealerships and shops use Parts Unlimited, which sells Motion Pro tools and cables, but they don't sell the custom cables. I couldn't get it from any dealership, I had to order it directly from Motion Pro.

Part number 01-0604 (http://www.motionpro.com/motorcycle/cable_partno/01-0604/). The cable in the picture is NOT what the cable looks like.

[86 Quad R]

the 400ex throttle block will be fine using the motion pro cable that wilkin250r posted. what you'll need to do is a little material from inside the throttle block that serves as a STOP. after doing this the carb slide will open fully.

[Rollscanardly]

Well she siezed up on me and when i finally got the heart to see why this is what i found, please let me know what you think happened....my crank is ruined, and possibly my cases too....havent taken the motor out of the bike yet to split the cases AGAIN =/

[Rollscanardly]

heres the piston that is also broken

[Rollscanardly]

Here is the plug i took out of it when she croaked.....i have some pics of the crank but on a different camera it has major indents in the crank part....im assuming the cases probably look bad....any ideas on what happened?

[Rollscanardly]

the plug:

[fireburns99]

Well i may be color blind but it looked like it was running lean, but i can't imagine it cause all that. It looks almost like a crank bearing went bad. I don't kow, you might as well pull it aprt and see how much needs to be replaced.

[86 Quad R]

what brand piston is that?

[Rollscanardly]

wiseco piston

[wilkin250r]

Naw, doesn't look lean. All the damage is at the bottom of the piston. If it was lean, the top of the piston would be overheating and cause the seizure by expanding too much. The bottom of the piston skirt is the coolest part, any overheating issues would be at the top.

I'm leaning towards a crank issue. I'm thinking a crank failure threw the rod out of whack, and pushed the piston against the bottom of the sleeve at an angle it wasn't supposed to, and that's what broke the sleeve and the piston.

As for a SPECIFIC crank issue, that could be any number of things. Main bearing, rod bearing, worn out, lack of lubrication, ect ect ect.

[Rollscanardly]

Well it was a new hotrods crank...yea ive heard all the horror stories...i guess now i have one of my own :/ not really sure what im gonna do now

[86 Quad R]

how many hours were on the build?

[Rollscanardly]

maybe 3 or 4 hours on all the bearings/crank/top end....not nearly enough =(
I broke it in over a 2 day period, and on the day i went and rode had it running maybe a total of 2 hours....she ran pretty well until what you saw happened....

[86 Quad R]

if the problem isnt the crank as mentioned i'd have to say that the skirt grabbed a port opening or there was too much piston to bore slop.