OzVMX Forum

Marque Remarks => Suzuki => Topic started by: brad747 on June 14, 2008, 11:51:30 am

Title: tm125 dg head
Post by: brad747 on June 14, 2008, 11:51:30 am
How about this?
Can any one tell me if this is rear or not??? and does it give you extra power or just the trick look??

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&mfe=sidebar&viewitem=&item=330242836799
Title: Re: tm125 dg head
Post by: Doc on June 14, 2008, 11:55:58 am
The DG 'cast' radial heads for a TM125 are indeed rare Brad. As for performance gains it's very minimal and nothing spectacular but it's the bling factor that will push the price up. Webco are about the best TM replacement head (apart from stock) but they don't have the nice looks of the radial type.
Title: Re: tm125 dg head
Post by: lukeb1961 on June 14, 2008, 01:37:03 pm
I don't know about the TM Doc, but on the PE175N the DG head pushed up the compression by a point and had larger finning. I very definately notice the difference when I put the DG head on!

Title: Re: tm125 dg head
Post by: TM BILL on June 14, 2008, 01:53:02 pm
I got one of these on one of my TMs only good for bling and heavier than standard  :-\
Title: Re: tm125 dg head
Post by: LWC82PE on June 14, 2008, 03:37:58 pm
well there you go, on a PE 175 they do work :). you must use high octane fuel to take advantage of the higher compression ratio though. i bet many guys dont do that, so the bikes ping like s**t and dont go any better then with the stock head and thats why you always see used DG heads with pitting and melting in the combustion chambers.
Title: Re: tm125 dg head
Post by: TM BILL on June 14, 2008, 03:52:48 pm
So will this one fit my PE 175 http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&mfe=sidebar&viewitem=&item=330242836799  ???
Title: Re: tm125 dg head
Post by: lukeb1961 on June 14, 2008, 07:19:37 pm
nah - 4-bolt on TM, 6-bolt on PE.
see http://members.optusnet.com.au/pe175n/Engine/DG1.jpg for the PE head
Title: Re: tm125 dg head
Post by: Doc on June 14, 2008, 08:26:00 pm
 :-X
Title: Re: tm125 dg head
Post by: lukeb1961 on June 15, 2008, 08:33:23 am
all I'm saying is that I heard people say that a DG head made no difference - yet when I got hold of one, I found it was, really, a noticeable improvement - at least the one for the PE175 C/N.
Title: Re: tm125 dg head
Post by: oldfart on June 15, 2008, 12:41:41 pm
By putting in a thinner head gaskets is a cheaper option  ;)
Title: Re: tm125 dg head
Post by: pokey on June 15, 2008, 02:20:01 pm
Any difference with the squish band or is it just a straight copy of the stock item with radial finning?

 seems a lot of cash for bling specially if its heavier with no actual performance increase
Title: Re: tm125 dg head
Post by: crs-and-rms on June 15, 2008, 03:11:27 pm
i like them for the bling look and im not ashamed to say so when i was young i always wanted one .i have two of them one for my  rm 125 n and one for my rm  125 t i also have a webco head for my rm 250 b they are much better for performance and cooling but are hard to find
Title: Re: tm125 dg head
Post by: Doc on June 15, 2008, 03:13:26 pm
On vintage MX bikes like TM, CR's, MX's etc an aftermarket head will not give you any 'feel it in the seat of your pants' type power increase. The bumping up of compression is common and 'may' make the bike a little snappier down low to ride but it's a trade off, this extra compression alone will not increase much except the bang factor. Aftermarket heads are heavy compared to stock and $ for $ the money would be better spent on a pipe or decent porting. Have a looky at these pages below I posted ages ago. Maybe with PE's and other non MX machines the difference is a more noticable but for a TM it's near all bling with little if any improvement. I run the T&M head personally but it's all looks  ;)
(http://farm4.static.flickr.com/3168/2579876080_72d4f20450_o.jpg)

http://www.vintagefactory.com/Elsinore%20Head%20Test.jpg (http://www.vintagefactory.com/Elsinore%20Head%20Test.jpg)
http://www.vintagefactory.com/Elsinore%20Head%20Test%201.jpg (http://www.vintagefactory.com/Elsinore%20Head%20Test%201.jpg)
http://www.vintagefactory.com/Elsinore%20Head%20Test%202.jpg (http://www.vintagefactory.com/Elsinore%20Head%20Test%202.jpg)
http://www.vintagefactory.com/Elsinore%20Head%20Test%203.jpg (http://www.vintagefactory.com/Elsinore%20Head%20Test%203.jpg)
http://www.vintagefactory.com/Elsinore%20Head%20Test%204.jpg (http://www.vintagefactory.com/Elsinore%20Head%20Test%204.jpg)
http://www.vintagefactory.com/Elsinore%20Head%20Test%205.jpg (http://www.vintagefactory.com/Elsinore%20Head%20Test%205.jpg)   
Title: Re: tm125 dg head
Post by: pokey on June 15, 2008, 04:49:02 pm
thanks Doc, good read.
Seems the aftermarkets dont have much on the stock head cept a few had better cooling  and the only reason to fit one is if you picked it up for a relatively good price.
Title: Re: tm125 dg head
Post by: Doc on June 15, 2008, 06:51:50 pm
that's the general impression I have on aftermarket heads too Pokey and yup, that little nos T&M unit above cost me about $80 all up. I baulk at anything over a $100 ;) The aftermarket heads may cool down quicker between races but that's irrelevant now as the bikes are 30 years old and rarely get ridden for more than 10 minutes on full noise. The cooling time not such an issue. Be different if they kept the bike cooler when running akin to watercooling temps but again in 10 minutes it ain't going to make bugger all difference. It's the weight factor that I dislike the most about most of them. The Webco heads do cool great (apparently) but they weigh twice as much as the stock head (factually) and all this weight is up high where it is unwanted. The thermal flow type Shinobi heads look super bling too but when you feel the weight of the head/rad/pipes and fittings you'd be fighting an uphill battle adding this much weight to a bike and then adding another kilogram of water on top of it all. Again it's all up high and not advantageous. I have to admit I really do like the look of my TM head and the FMF porcupine styles but they don't do much else. Reshape and polish up the stock item and you'd be onto a better thing ;)
Title: Re: tm125 dg head
Post by: pokey on June 15, 2008, 08:17:56 pm
Bought a odyssey which had  DG  Gold anodised head on the , went like stink and looked trick  but i suspected the head was just bling like most of the stuff from DG . still got hot after a good session in the mud.

 Those porcupine heads do look good  but only ones ive seen are out of my price range . think I will stick with a stock head  unless i find am ocelot or such being used as a door stop
Title: Re: tm125 dg head
Post by: lukeb1961 on June 15, 2008, 08:29:39 pm
My DG head was zero cost (gift; had been sitting in a shed for 25 years) - so bling and some perf increase at zero cost was nice!
Title: Re: tm125 dg head
Post by: firko on June 15, 2008, 08:39:57 pm
I know taste is a personal thing but I reckon that those gold anodized DG heads look ugly. Whetherany of those aftermarket heads actually work is doubtful. I tried GYT, DT2MX, Webco and a modified stocker that I'd totally filled the combustion chamber with weld and then Peter Reynolds had designed a combustion chamber to suit the Gary Treadwell porting and Peters own pipe. The first three heads showed no improve in performance at all and the modified head showed a bit more punch down low but not enough to warrant the hours of work. We came to the conclusion that the combustion design design isn't as critical as some gurus will tell you.
Title: Re: tm125 dg head
Post by: pokey on June 15, 2008, 09:14:01 pm
Interesting hearing the experienced. with the small bores im thinking weight to be a big issue and if its only a few laps  i cant see heat being that big of an issue .

 i guess if you dont have a budget and are racing for sheep stations yeah get a good head and tune for it to get the maximum amount of performance but sheesh aint VMX all about a bit of fun ? tis for me .
Title: Re: tm125 dg head
Post by: lukeb1961 on June 18, 2008, 10:42:47 pm
I know taste is a personal thing
Got it in one. I think they're absolutely right and look great. It certainly makes a difference on the PE175N. I don't have to doubt it. I know first hand and it has nothing at all to do with the chamber design. Doc knows they make no difference on the TM so that's excellent info. As to combustion chamber design, I'll go read Blair or Dixon and listen to Lozza's opinions too :-) All fascinating stuff. It'd be a ton cheaper and easier to go on a diet if you wanted to go faster, of course!
Title: Re: tm125 dg head
Post by: Lozza on June 19, 2008, 08:09:22 am
Geez Luke hope your not putting me in those blokes league are you???  ;D If your under the impression that head design has no influence on output HRC, VHM,KTM and even Treaders mate Brian Stockman are all wrong then. I can tell you on an RS 125 we have run 17.5:1 compression with no dets(it killed over rev & a bit of top end though), had enough drive of turns to leave a GSX-R750 for dead. Head design and shape has a big influence but it's not in the way you might think.
Title: Re: tm125 dg head
Post by: Doc on June 19, 2008, 08:25:26 am
Luke the performance felt 'exactly the same' with or without the aftermarket head. I am not saying they don't work I am just saying you won't notice any performance gains fitting an aftermarket head to a TM125. The extra weight doesn't justify any extra cooling properties for a bike ridden for such short periods. If 'anyone' can design a head that will give me a 'felt in the seat of my pants type power increase' for a TM125 'without' simply raising compression and running hi-octane fuel I'll stand corrected  ;)
Title: Re: tm125 dg head
Post by: Lozza on June 19, 2008, 09:23:11 am
If you supply the pistons it's easy no problems ;D