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MP 7.5 Sports stock GX-21 engine

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S

SchumacherCat

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sup, i am thinking weather if i should bye the sports edition of the car with the stock GX-21 engine with it, i would like a complete package wich it is, but i had a buggy with a GX-15 engine in it and had some minor problems like the muffler became loose often, and some trouble starting after it stalled, I am on a buget with my one my own cash and dont have enough cash to buy a seperate motor, is it worth buying he car with the stock GX-21 in it or save up and get a higher class like the GS-21R? I am not going to race it professionaly jsut for fun, mayber ill bring ti to a few races, =but i want to go fast! came u help me decide, i gtg
 
if u wanna go fast put a xtm 24.7 on it. its pretty cheap compared to other motors. it sick fast. the only thing is, is that it is not legal for racing.
 
thanks for the tip, but i would like to know if the GX-21 is an alright motor quality wise and would make it run at a decent speed, and if it has average porformace so be it.
 
It's an alright motor, it tunes well though but is fairly weak for a .21- almost OFNA Force .21 weak.
 
The only problems I've had are tghe needle settings changing for some reason. I had to chage the o-rings on the needles and they have been fine ever since.
 
Schu, the GX-21 is a base engine. It's got enough power to make the 7.5 Sports quick and fun to drive, but it's definately not one of the more powerfull big-blocks out there. I read in an article of RCCA that the engine lacked some low-end power but it pulled pretty decent on the top end (which seemed right on), and stock the buggy topped out at 45mph (which to me seems a little high).
I've got a buddy that has the 7.5 sports and I've driven his, and it is fun to mess around with, but the first major upgrade I would do is replace that engine.
The only problem he's had out of it are the rear shock shafts. He was just running it around one day and bent one of the shafts into an L shape. Crap, I didn't even see it hit anything! He probably hit a rock though.....some upgraded Kyosho shocks later and the problem hasn't happen again so far.
It handles decent and jumps great! It's easy to maneuver through the air...it stays pretty flat, no bad nose-up or nose-down problems.
 
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Yeah about those Sports shocks, they're terrible, my father did a few jumps and they already bent, my Hyper 7's shocks are about that thin and never bent- must be the material in the shaft.
 
yeah, i might get some thicker springs for the shocks, also am getting those rubber insilators to put around the shaft so dirt doesn't get in them, also is the EB4 rtr better than the kyosho sport overall or not as good or the same, they both cost 500 and i am not sure which to get, the Eb desnt have ball bearings or a sercure battery case.
 
The 7.5 sprots is an allright buggy.. however.. i would go with an Ofna, if your getting a RTR.. nothing against Kyosho.. cuz they make a bad ass buggy.. which is what i race with.. but the Kyosho Sports is a lowsy, slap something together so we can get some of the RTR sales from Ofna deal... they just slapped something together.. and it isnt good.. the shocks.. the shock towers.. the chassis.. all weak.. the car comes with a plastic spur gear.. and the diffs only have 2 planetary gears in it rather than 4..

Just my opinion.. but my buddy will testify. cuz he has one.. and it is no longer a sports.. with all the stuff he had to replace on it allready..

Hyper 7 RTR, or 9.5 RTR..
 
dgrobe, your last statement about your buddy's rtr says it all. Kyosho made the rtr so that a person could own one without the hefty price tag for the kit. For the price conscious individual, the rtr simply offers an entry level opportunity into 1/8 scale buggies. As your driving skill improves, you can upgrade this buggy and literally transform it into a kanai buggy. The Kanai buggy is definitely the best performing 1/8 buggy period, with a proven track record, this should be no news to you because its what you race with. Now maybe you had $1200-$1300 laying around to set yours up correctly, but the majority of people dont have that kind of cash at their disposal, so the rtr is an excellent choice as it allows you to spend a little at a time while enjoying the hobby at the same time.
 
I actually dont own a Kanai buggy, mine is a Kyosho 7.5 kit form buggy, that i bought used from a guy, here.. and it came with everything on the buggy, all the hopups allready..

I was simply stating.. that the Ofna RTR's are better than the Kyosho RTR, and in order to make the Sports version of the buggy, and Kanai buggy, you would probably be better off buying a Kanai buggy. Ciz you will have to replace everything.

My point was to simply state that while the Kyosho RTR buggy has a nice price tag on it.. you will be happier with a Ofna RTR, tougher, thicker shock towers.. steel spur gears, steel ring and pinions.. the kyosho has aluminum ring and pinions.. which strip easier.. now the Kit form of the kyosho has all the better stuff.

Ofna 9.5 RTR 499.00
Ofna Hyper 7 RTR 469.00
Kyosho RTR 449.00

Just stating what i know.. and i see the Ofna RTR buggies flip, and crash, and tumble.. and all that.. and never seem to break.. but my buddies went 1 jump, or 2.. and bent he shock shafts..
 
Originally posted by dgrobe2112
The 7.5 sprots is an allright buggy.. however.. i would go with an Ofna, if your getting a RTR.. nothing against Kyosho.. cuz they make a bad ass buggy.. which is what i race with.. but the Kyosho Sports is a lowsy, slap something together so we can get some of the RTR sales from Ofna deal... they just slapped something together.. and it isnt good.. the shocks.. the shock towers.. the chassis.. all weak.. the car comes with a plastic spur gear.. and the diffs only have 2 planetary gears in it rather than 4..

Just my opinion.. but my buddy will testify. cuz he has one.. and it is no longer a sports.. with all the stuff he had to replace on it allready..

Hyper 7 RTR, or 9.5 RTR..
Click to expand...

I am his buddy and I will testify that my RTR Sport buggy aint a RTR sport buggy. I bent the rear shock shafts and the chassis. I am a DIE HARD KYOSHO racer, but buy the pro version or Kanai. If not, get the OFNA hyper 7 RTR. All thier stuff is beefier.

...I forgot to mention, that I had problems with my motor too. I grenaded my rod bearing...:ahh:
 
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yep.. and that motor that comes with the Kyosho RTR, also.. everything in keyed for that motor.. if you mess up tyhat motor.. you need to replace everything.. new flywheel, bearings.. clutch, clutchnut, clutchbell, everything needed replacing.. even the header..
 
Originally posted by dgrobe2112
yep.. and that motor that comes with the Kyosho RTR, also.. everything in keyed for that motor.. if you mess up tyhat motor.. you need to replace everything.. new flywheel, bearings.. clutch, clutchnut, clutchbell, everything needed replacing.. even the header..
Click to expand...

$110 dollars later I had replaced the motor with a new Ofna Hyper 7 8port and all the equipment listed above.
 

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