BuggyMasters.Com - An On Line Mini Buggy Forum and Go Kart Forum

Go Back   BuggyMasters.Com - An On Line Mini Buggy Forum and Go Kart Forum > General Mini Buggy and Go Kart Forums > Mini Buggy General Discussion

Mini Buggy General Discussion General Discussion forum for Mini Buggies. (American Sportworks, HammerHead, Carter, etc)

Reply
 
Thread Tools
  #201  
Old 01-13-2018, 12:57 PM
SYCARMS's Avatar
SYCARMS SYCARMS is offline
Supporting Vendor
 

Join Date: Sep 2009
Location: Senatobia, Mississippi
Posts: 3,051
Default

It appears your using a new plug. Use an old but good plug that is already colored. If you don't have a good old colored plug then drive the buggy until the porcelain is colored then redo the test. It will be much easier to read. You will be looking at the base of threads, porcelain and ground strap. Color should be a brown. Check and make sure you do not have a vacume leak at the intake. What carb are you running?
Reply With Quote
  #202  
Old 01-13-2018, 03:43 PM
Pripyat Pripyat is offline
Lite Contributor
 

Join Date: Aug 2017
Posts: 97
Default

That may be the oldest plug I've got. There is no vacuum leak. 30mm pumper cvk.

Will an EGR head work with a non-egr valve cover? I'm having a hard time sourcing a big valve head without EGR.
Reply With Quote
  #203  
Old 01-13-2018, 06:38 PM
SYCARMS's Avatar
SYCARMS SYCARMS is offline
Supporting Vendor
 

Join Date: Sep 2009
Location: Senatobia, Mississippi
Posts: 3,051
Default

Generally the EGR heads have smaller valves and smaller runners. Non EGR heads are out there I have them in stock with larger valves and runners. Put your stock carb on with around a 125-130 main jet. That 30mm carb is too big.
Reply With Quote
  #204  
Old 01-14-2018, 09:25 AM
Pripyat Pripyat is offline
Lite Contributor
 

Join Date: Aug 2017
Posts: 97
Default

I won't be messing with the buggy much this week but I do have some questions -

I emailed SYC about purchasing a cylinder head through him. After some discussion I realized that if I order one from a shop that does engine work I would want to go ahead and get a port/polish from someone who knows what they are doing. But, I want to play with the big valve head in its stock form and see what the gains are just from the larger ports/valves before the port/polish. So currently I'm trying to source a well made head with large valves to play with. If I find that I'm still wanting more I'll seek a port/polish for the new big valve head.

But, I cannot find a name brand big valve head (58 through 61mm) without EGR just by searching on the internet. Why can I not find a Taida or NCY non-EGR cylinder head with 28/23 valves? I have spent hours searching.

I didn't follow up with SYC to find out what brand he stocks but the only 28/23 non-EGR head I can find is one on ebay under the brand "Charmo". Interestingly it says "Taida" as being the brand. Maybe it is a clone of the Taida head? Interestingly the seller on ebay is the same one I got the terribly cast, crappy head from. I will cry if I order the Charmo head and it has the huge castings extending up into the ports around the valve stems like the other cheap head.
Reply With Quote
  #205  
Old 01-14-2018, 09:46 AM
Shadowfocus603 Shadowfocus603 is offline
Lurker
 

Join Date: Dec 2017
Posts: 11
Default

http://www.scrappydogscooters.com/12...rformance.html
It's been almost 10 years since I ordered the head at the top of that page so I don't remember much about the casting but I can say it made damn good power. The owner Rick is a great guy that I met through the grapevine when I lived in Vegas.
Reply With Quote
  #206  
Old 01-14-2018, 11:45 AM
Pripyat Pripyat is offline
Lite Contributor
 

Join Date: Aug 2017
Posts: 97
Default

I saw that head but I was worried it had a large combustion volume (for 63mm) and i'd end up better off with slightly smaller valves with a combustion chamber designed for 58 or 61mm.
Reply With Quote
  #207  
Old 01-14-2018, 11:51 AM
ckau's Avatar
ckau ckau is offline
Heavy Contributor
 

Join Date: Dec 2009
Location: central North Carolina
Posts: 889
Default

Have you looked at the pilot jet? I had to change up on the pilot in order to get a acceptable plug reading. I lost my database awhile back so everything I state comes from memory and that is not totally reliable but I think I ended with a 145 main and a 38 pilot. The 30mm carbs I purchased did not have any main or pilot jet sizes stamped on them At first try I could immediately tell they were way too lean. Using a wire gauge, the supplied main was about a 135 and the pilot was some thing like a 28 so I purchased a wide range of main and pilots sizes and started with a sophisticated wild ass guess.

keihin jets part # main- 99101-393, 140 to 160 ranges
pilot- N424-21 35 to 50
This is on a motor 155cc, 30mm port matched head, and a 7/8ID x 28" long exhaust. Your motor configuration will make a difference in jetting.
Your moving along faster than I can respond to the posts but hopefully this info may help.
Reply With Quote
  #208  
Old 01-14-2018, 12:35 PM
ckau's Avatar
ckau ckau is offline
Heavy Contributor
 

Join Date: Dec 2009
Location: central North Carolina
Posts: 889
Default

Quote:
Originally Posted by Pripyat View Post
I saw that head but I was worried it had a large combustion volume (for 63mm) and i'd end up better off with slightly smaller valves with a combustion chamber designed for 58 or 61mm.

I found the larger cc heads work fine as long as you supply enough air in and out. A large uni, a 1-3/4" id x 6.5" long velocity tube, 30mm carb and 7/8" id exhaust works great. I always focused on packing as much air and fuel as physically possible into the head and enough pipe to move the a/f out. I think it like a air pump, the intake, chamber and exhaust matched to move large volumes of air efficiently. There's tons of variables here but that's a basic concept.
Reply With Quote
  #209  
Old 01-14-2018, 02:25 PM
Pripyat Pripyat is offline
Lite Contributor
 

Join Date: Aug 2017
Posts: 97
Default

I just realized that the head on scrappydog is EGR. What does using an EGR head entail? New valve cover?
Reply With Quote
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 11:34 PM.


Powered by vBulletin® Version 3.8.3
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.