86atrack4

I'm using a 8 port in both my warhead and my hyper 7. The warhead is 10.5 lbs, with a 14t cb it has some good bottom end. It really can scream when its on the pipe.

jokerplaya

I have recently aquired this engine from a friend expecting it to need a rebuild soon
but today i ran it and it seemed fine.
Im use to haviving new people come into my hoby shop with trx 2.5s and ask if there toast (witch they may feel tight but they are usualy toasted)
so i think may fine feeling fingers cant tell if this one is close to toast.

how tight are your piston and sleeves.
is this motor generaly looser then other motors?
any advice would be great

86atrack4

I would keep running it until there is a reason to rebuild. If the engine keeps a tune and has good power with good idle, I would say keep using it!

os18rush

what should i set my mid speed needle at? i just got my hyper 8 port back together with a new jp-1 pipehas fantastic bottom end but when i romp it from idle it studders then slowing climbs for a while then just rips.

luniemiester

Set it back to stock first then experiment by turning it in a quarter of a turn at a time ( remember to alter your low speed screw the same way to keep your low end tune - if you turn the MSN in a quarter of a turn you need to unscrew your LSN a quarter of a turn)

To reset the jet take off the HSN fitting and you will see inside the mid range needle. There will be 4 holes drilled in this needle

Wind this out till its flush with the outer body of the carb and then turn it slightly in until the hole in the needle lines up with the hole for the HSN. Scribe the carb body so you have a reference if you adjust the needle.

Put it all back together and check that the HSN and the LSN are steup correctly then try altering it as decribed - a lot will depend on the pipe you're using to get it right. If you get lost just wind it back to the stock and try again.

The JP 2 is better than the JP 1 on the 8 port

Hope this helps

jonnymac

How experienced are you with 3 needle carbs?
If your good with them then then adjust the mid needle. As mentioned above it doesn't work like normal needles and requires full 1/4 turns. If you haven't done this before i recommend leaving it at factory until you know more on it as it can screw your performance and it can be difficult to sort out afterwards.
There are a few old thread on here telling you in detail how to set them up but definatley dig them out and fully understand them before adjusting it.

john211420

my hyper 21 drinks through fuel it si 25% and it over heats things like my baring clutch and thinck it done damage to pull start

jj48

Hey Guys I was looking for some info on the Hyper .21 8 Port engine. From reading the Forms I think I understand the 3 needle carb but I still have a issue getting the engine started. For one I don't have a starter box ...yet anyways. What happened is the pull cord snaped and I removed the pull cord houseing. Now what is left is a 1/4 shaft that comes out of the engine. That shaft can be slid out, this is normal? I bought a roto start and well it did not quiet match up but was able to make it work. The engine will whirl over but it acts like there is very little compression. Could this be due to the fact that the roto start houseing is not making a really good seel? I had a buddy as well try a one way bearing on his and he got the same symptoms. Is this normal that without a seel around that shaft compression is lost? I ordered a correct pull cord and hope that will fix. Let me know if I am on the correct page here.

Thanks
jj48

REVO X

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I have this Engine [link]http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXCLD7&P=7[/link] ... dont know if it is a Mach .21 what you call it, was wondering if this will work [link]http://www.southeastrc.com/Items/StdItemView.aspx?lookup=OFN53006&adp=froggle1[/link] in it?

jonnymac

That engine is a Hyper .21 4 port, and yes that piston/liner kit will fit.

cabv19

Hi,

I am a new member and got from a friend a broken down hyper .21 8 port.

I am planning to restore a Ofna gtp single speed …. Would this be a good engine for this car and were can I find the complete rebuilding kit ???? …. Also what pipe would work for this engine?

Thanks…

jonnymac

[link=http://cgi.ebay.co.uk/Ofna-Hyper-21-8-port-Piston-sleeve-w-conrod_W0QQitemZ130175277301QQihZ003QQcategoryZ191 68QQrdZ1QQssPageNameZWD2VQQcmdZViewItem]Here[/link] you go.
Welcome to the forum.
I have no idea what a OFNA GTP is sorry so can't answer your question on that.

rologti

Hi,

My Hyper 7 is running an Hyper .21 8 port, for pictures i could say it's race, but i'm not sure.

My story....as i only have a hand starter, it was really dificult to start the engine the first 8 times...so i didn't break in like a lot of people do (start it, 3 minutes, stop it until it cool down, and do it again for about 5 times). The first time that it started (after about an hour and a half), i've think " i'll never start this engine again, so i'm going to leave it running as far as i can"...so i rich the needle a bit more and leave it running for about 2 tanks, after i've start leaning it (about 1/4 of turn), and let the engine temperature raises, then after 2 minutes, rich the engine again so the engine cool again, i've continue doing this and reaching higher temperature, until i've reach about 100°C (that was in the 10th tank)...i have to stop because my girlfriend was really pissed off.

The next day, after work, i try starting it again, and after half an hour it started, this time, i've go back to the break in settings that shows the manual, and start using the buggy with shorts acelerations at about half throtle, so it could warm up and then after about 3 acelerations i leave it cooling, and then again and again...this method for about 4 tanks.

Next day, the same for about 4 tanks but with a bit more throtle...and the next again, then i've start to lean the engine a bit, until it sound good, and the temperature dosen't goes higher than 115°C, with longer acelerations at full throtle

Now the engine starts in about 5 minutes, but on 50% of the times i've have to tune it again, the feeling that is left is that the engine lose the set up almost always, but i have to keep in mind that sometimes the temperature is about 33°C and in other cases about 18°C.

The engine once it's running OK, runs great, very high end, and some nice take off. But i think it still needs half a gallon more to be ready to race, also because i don't want to stress it yet.

After all of these story, i've got a 2 question. 1) the way i've make the break in is too wrong??? should i have more patience for the next engine??? and 2) To avoid the lost of the set up, should i change the o-rings, or is just because the temperature changes???

Thank's guys

sidv13

I used to run the hyper 8 port race on my hyper 7 and it I will say that I personally did not like the three needle carb and a friend of mine gave me a os carb that fit it and it ran awesome I never had any tuning issues with it at all and it had no bottom end power issues that I ever noticed. anyways just my two cents

rologti

Do you know wich carb could fit these engine, so i could ebay it???