Mudhead 208R - top speed? seems slow....

[jpcjguy]

Hi all,

Just picked up a 2015 Mudhead 208R for the kids. Already have a hammerhead 80T but it does not have reverse. The thought was this was going to replace it. Somehow it feels considerably slower than the 80T. Of course I cannot do a direct comparison as I am in the process of putting a new DuroMax electric start on the 80T. I got in it and went up and down the street and according to my GPS on my phone, my top speed was 18-19 mph. Of course I don't know what the 80T did before dismantling it - but from what I recall it just seemed faster. It also had a lot of "monkeying" from previous owners on it - not all good - but it was the first buggy so I had no frame of reference. (Disclaimer: I am 6'5" 240lbs - so I am not expecting rocket speeds)
What can I check? Both have stock 16x7-8 rear tires, but the mudhead are basically bald.

Thanks,
Joe

 

[KartFab]

i did a quick search on this little guy and it looks like the engine is a LCT 208cc engine, and it states it has a automatic/CVT transmission. This tells me two things:
1) engine should probably go 3600-3800 rpm
2) CVT should have a belt on it.

A review of the 2016 model said it should go 30-36 mph....

SO, time to do a little investigation. I would start with the obvious things, the throttle travel, and the CVT belt.

Grab that throttle lever on the engine and pull it to max throttle, then take a mental note of where it goes to, then step on the gas pedal, does it go to full throttle or only part? (you can do this with the engine off, we are just looking at throttle lever travel). Is there a throttle stop bolt too far in preventing max travel, or perhaps a stretched out, loose throttle cable, or something like this?

Next, pull off the CVT cover on the engine shaft side and inspect. I dont know what kind of CVT it has, but it may have a 30 series torque converter on it. pictures will help identify it. If it is a 30 series, it would have a 3/4" width belt on it. As a belt wears out, it may stretch (the crappy ones do) and become skinnier, not allowing the engine to accelerate properly or even reach the desired final drive ratio. If it is not the belt, there may be some sort of issue with the CVT itself, not allowing it to transition into the final drive ratio. Sometimes a lack of maintenance will make the moveable drive sheave stick in the initial drive ratio. Some CVT's have a speed limiter in them that prevent the weights from transitioning the CVT into final/overdrive. Only way to tell with that is to disassemble the drive unit on the CVT and inspect/clean.

Good luck, and post up some pictures. We may even be able to give you some tips to make the kart faster than its advertised speed muahahah! But we will see if we can get it at least to the speed it should be going.

 

[jpcjguy]

i did a quick search on this little guy and it looks like the engine is a LCT 208cc engine, and it states it has a automatic/CVT transmission. This tells me two things:
1) engine should probably go 3600-3800 rpm
2) CVT should have a belt on it.

A review of the 2016 model said it should go 30-36 mph....

SO, time to do a little investigation. I would start with the obvious things, the throttle travel, and the CVT belt.

Grab that throttle lever on the engine and pull it to max throttle, then take a mental note of where it goes to, then step on the gas pedal, does it go to full throttle or only part? (you can do this with the engine off, we are just looking at throttle lever travel). Is there a throttle stop bolt too far in preventing max travel, or perhaps a stretched out, loose throttle cable, or something like this?

Next, pull off the CVT cover on the engine shaft side and inspect. I dont know what kind of CVT it has, but it may have a 30 series torque converter on it. pictures will help identify it. If it is a 30 series, it would have a 3/4" width belt on it. As a belt wears out, it may stretch (the crappy ones do) and become skinnier, not allowing the engine to accelerate properly or even reach the desired final drive ratio. If it is not the belt, there may be some sort of issue with the CVT itself, not allowing it to transition into the final drive ratio. Sometimes a lack of maintenance will make the moveable drive sheave stick in the initial drive ratio. Some CVT's have a speed limiter in them that prevent the weights from transitioning the CVT into final/overdrive. Only way to tell with that is to disassemble the drive unit on the CVT and inspect/clean.

Good luck, and post up some pictures. We may even be able to give you some tips to make the kart faster than its advertised speed muahahah! But we will see if we can get it at least to the speed it should be going.

Thanks for the great response! I did look at the throttle setup. It appears that it is ok now. The throttle return spring was broken so I snagged that off of the old motor from the 80T. The "arm" on the gas pedal that holds the cable end appeared to have been either broken off and rewelded wrong or bent down because the angle was such that when you hit the gas it did not actually pull on the throttle cable until you got past 1/2 way! I bent it to match the 80T (appears to be the same part).
I also have the following tach: https://www.amickssuperstore.com/DTI_2_Cycle_Two_Stroke_Hand_Held_Tachometer_p/dti%20tech-tach%20tt-20k%20tach.htm and attached it to the spark plug with and maxed out the throttle and it went ot 3850 rpm or so. Of course now that I am recalling - not sure if I used the pedal or moved the throttle lever by hand. Will have to review.
It is a 30 series CVT - I will have to pull the cover and inspect. I will grab a video of it going up and down also.
I have attached a pic of the kart - didn't think I did too bad on the price - $550. I guess we will see

Thanks!
Joe

 

[KartFab]

glad you were able to fix it, and you replied and let everybody know!

 

[jpcjguy]

glad you were able to fix it, and you replied and let everybody know!

Actually I have not fixed it yet. What I listed is what I had done already and it was still slow.
This morning before work I went outside and popped the cover and looked at the belt.
I am pretty sure it is the wrong size. Attached are pics that shows the belt number and the slack in it. I can practically take it off by hand.
Here is a video of it from idle to full throttle: https://photos.app.goo.gl/mE3f3SqF43mVictg8

 

[KartFab]

engine sounds fine, governor is kicking in under little to no load. drive unit is not going into full overdrive. Before you get a new belt, that one 'looks fine visually'

check this site out and measure your center to center distance and driven unit diameter
https://www.gokartsupply.com/tcbelts.htm
According to your belt, the center to center should be between 7-1/8 to 7-3/16"
If your belt stretched, you can tell by measuring the outer circumference, which should be exactly 28 21/64"

If your center to center distance is too small, and your belt is okay, you might want to see about simply adjusting your engine forward so you get the right center to center distance.

A properly functioning torque converter should show the belt edge going beyond the outermost part of the drive unit in overdrive. It is not going to overdrive right now. Could be an easy fix by sliding the engine forward.

 

[jpcjguy]

engine sounds fine, governor is kicking in under little to no load. drive unit is not going into full overdrive. Before you get a new belt, that one 'looks fine visually'

check this site out and measure your center to center distance and driven unit diameter
https://www.gokartsupply.com/tcbelts.htm
According to your belt, the center to center should be between 7-1/8 to 7-3/16"
If your belt stretched, you can tell by measuring the outer circumference, which should be exactly 28 21/64"

If your center to center distance is too small, and your belt is okay, you might want to see about simply adjusting your engine forward so you get the right center to center distance.

A properly functioning torque converter should show the belt edge going beyond the outermost part of the drive unit in overdrive. It is not going to overdrive right now. Could be an easy fix by sliding the engine forward.

Figures- I ordered a belt this morning.

But wait - Looking at the parts diagram, the swing arm for the motor does not adjust. Attached is a pic of the part.


I will double check the measurements when I get home.

 

[jpcjguy]

So it appears that the mudhead and the 80T are both a hair under 7" - 6.96" according to my digital caliper. See the attached pictures. The one with the digital is set to 7.126" (7 1/8). As you can see my distance is a little smaller than that.
It actually matches my 80T - and I runa 203589 belt on that. This is a smaller belt than the 203590. I guess that is the difference.
What I ordered is a "Rubber Go Kart Belt Drive Clutch For Hammerhead 80T and TrailMaster Mid XRX Go-Karts 9.100.018-725" off amazon because I can get it with prime and I need it by thursday. Taking the buggy on a trip for the weekend.
I guess we will find out if the 9.100.018 (hammerhead part number) and "725" matches the 203590 or the 203589......

 

[Denny]

Stick to using Comet brand belts they will last much longer and work better than the other no name brands. Experience talking here.


Denny

 

[landuse]

So it appears that the mudhead and the 80T are both a hair under 7" - 6.96" according to my digital caliper. See the attached pictures. The one with the digital is set to 7.126" (7 1/8). As you can see my distance is a little smaller than that.
It actually matches my 80T - and I runa 203589 belt on that. This is a smaller belt than the 203590. I guess that is the difference.
What I ordered is a "Rubber Go Kart Belt Drive Clutch For Hammerhead 80T and TrailMaster Mid XRX Go-Karts 9.100.018-725" off amazon because I can get it with prime and I need it by thursday. Taking the buggy on a trip for the weekend.
I guess we will find out if the 9.100.018 (hammerhead part number) and "725" matches the 203590 or the 203589......

But are you sure that the belt you ordered is the correct one?? Are you sure its for the same center to center as what you have? It sounds very generic to me. Hopefully it works out for you, but personally I would buy genuine comet with the known numbers so that I know what I am getting is correct for my setup

 

[jpcjguy]

I agree on buying genuine Comet brand, but unfortunately it is not available (for a semi-reasonable cost) for 2 day shipping. So I tried an off brand. Worst case, I return it. We are heading out of town on Friday and taking the buggy so I took a chance.....