Jump to content

Trinty 420 Seized! Whats next? Cubs?


spoolnvr4

Recommended Posts

you are better off going with some cubs. If you go with a +4 think twice about going with a hotrods one because they have been having a LOT of broken ones. The company split now and I think wiseco is having someone build cranks just for them but they are more around $650 so with that price you might as well go with a bigger crank because they are around the same price. The trinity 420 big bore kit sucks. The sleeve is so big that the transfer ports are almost nothing and thats where a lot of your power is made. Also because the piston/sleeve is so big they over heat very easy in glamis where I ride. You are much better not paying the big bucks to resleeve it and just buying some cubs in any size you want. Even a 65bore stock stroke will kill a trinity 420. Go with the 68 bore cubs and whatever crank you can afford becuase the 68mm pistons and the 65mm ones are the same price. Also clean that case out really really good before you put it back together too.

Link to comment
Share on other sites

I really wanted to get a set of Cubs. I was going to have the Crank redone with new rods. Is it the rods they were using that are bad. If i have the Crank rebuilt, any particular rods to go with? Is it better to buy an assembled crank already done.

 

Trinty wants

-$100 Ea. Rod

-$65 True and weld

-$130 Labor

 

Approx $400

 

Is there a significant benefit to using a 4mm long rod Vs. Standard. I see the Cubs advertised on eBay all were setup for the 4mm long rod. Are they available to use with a standard crank(Is standard pistons used instead then?)

 

eBay link Cubs/Topend kit

http://cgi.ebay.com/ebaymotors/BANSHEE-4-m...1QQcmdZViewItem

eBay link Cubs/Top end/Crank

http://cgi.ebay.com/ebaymotors/BANSHEE-POL...1QQcmdZViewItem

 

Now if i am going to spend $600 on a 4mm Long rod liek the kit above. Would a 4mm Stroker from Trinity be better for the same price? Or shoudl i just rebuild the stock crank i have. When you purchase a crank from Trintiy or others does it come with Bearings?

 

Thanks

Link to comment
Share on other sites

Everyone gets confused about long rods and strokers.... long rods changes the geometry and is suppose to reduce side loading on the piston. It does not increase the engine size, and makes no power difference. It is just for reliability. Strokers, such as +4, +7 ,+10 etc. are a longer stroke, this does increase the displacement and does make more power. Also most stroker cranks come with long rods on them already.

 

If you are planning to get Cubs, I would not rebuild your old crank... for a little extra money you could get a +4 stroker crank with long rods on it. Then get your Cubs for a +4 and it all just bolts together... easy...

 

If you are going to reuse the 420 top end then ya go as cheap as you can on the crank. Get yours rebuilt with long rods or find a used on. There are lots of stock cranks around from everyone who has gone stroker.

Link to comment
Share on other sites

Sorry but the link that includes a crank isn't working for me so I can't see what all is there. I do know if you want to use the Trinity head you have now it will need new domes. Those are good heads but the domes for the 420 are different.

Link to comment
Share on other sites

Sorry but the link that includes a crank isn't working for me so I can't see what all is there. I do know if you want to use the Trinity head you have now it will need new domes. Those are good heads but the domes for the 420 are different.

440967[/snapback]

 

ohh ok, it is an ebay link to 4mm Cub Cylinder/pistons/crank. If i went with a stock crank and Cheetah Cubs... how many CC will that be. Are the Cubs pistons larger than stock???

Link to comment
Share on other sites

I belive the Cubs come in either 66mm and 68mm bores. If you go 68 with a +4 crank that gives you a 421. The 68 with a stock stroke crank is a 400. If you need a crank anyway go to the +4. If you don't you'll wish you had. The +4 drops right into the cases with out any case mods, so it's just as easy as putting in a stock crank.

 

What you will need is:

 

- Cub cylinders, they come with pistons and top end gaskets

- +4 crank, comes with bearings but not seals

- crank seals

- water pump and side cover gaskets

- new domes for your head

 

I think that should get you running again but in your pics it looks like you have stock carbs and reeds. You will also what to upgrade those as well... probably go to 34 or 35mm carbs and some V-Force reeds. It would run with the stock carbs if you can't aford to do it all at once... but it'll cost ya in power of course.

Link to comment
Share on other sites

cubs come in 65 and 68 mm stock versions ,the 65 will rev higher,and in theory the 68 will make slightly more torque for bigger riders . a 65 mm cub is actually a 358cc displacement ,i have a drag ported stock stroke 65 mm cub setup and its nothing short of unbelivable power considering its size ,id confidently drag up against any big bore out there .id recommend that yo u speak with passion racing about his kits ,keep in mind ,youll need other mods to accent it though, like bigger carbs intakes /head mods ..and such . :bolt:

Link to comment
Share on other sites

on the hot rods +4 stroker cranks, the welds are breakiing that hold the crank webs to the rod pins. if you do buy one, I would have some one go over the factory welds and re weld them, I had cubshee over on planet sand true and reweld mine and have not had anymore problems as of yet. I would never buy anything else other than a cub motor, I had a viteos big bore kit for awhile, then I went to my cub and the power is night and day differance, I have raced t-rex bikes +7 +10 strokers etc.. and they have a hell of a time keepin up.

another good builder to contact would be jeff from FAST, he has anything and everything you could imagine for a banshee, and I taked to him the other day and he has started welding the hot rods cranks before he evan sends them out.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...