monty conrod alternatives

[dutchtwinshock]

i was looking for a new monty 360 conrod kit .
I was asking myself if someone ever found a altanativ conrod witch also fits?

I saw that a honda cr250 conrod has almost the same dimensions.Accidental ecactly the same used in the cota 314
1 mm longer(125mm) and has 2mm thicker big end as the original 360 conrod.small end is the same
would possible drilling bigger holes and a thicker base gasket.

A 1978-84 ktm 250 conrod should be also fitting

[montynut]

I am pretty sure Jared (SW Montesa) can help you out or John (RM Montesa) and if not try here
http://www.kevinbreedonracing.co.uk/products_conrods.asp

I have had excellent service from all of them

[mx250]

Some else might like to confirm this but I think the 250/360 Cappra rod is the  same. The different stroke comes from different big end positioning on the crank (longer stroke).

[firko]

The different stroke comes from different big end positioning on the crank (longer stroke).

Correctomundo Graeme...The biggest phurphy around is the belief that rod length has anything to do with the stroke of an engine. Simply put, the stroke's determined by the crank throw or as you say, the positioning of the crank pin on the flywheel. I know it's a sway away from the subject but the rod/stroke thing really annoys me.

[dutchtwinshock]

i asked Kevin breedom already, he had for the 360 only a special competition conrod (italkit),very expensive one (260 pound)witch also need a special piston.

Together with him i came along that ktm 250 conrod witch is exactly the same as the montesa 360 conrod.

I saw one at solomontesa.....  but ones i waited 4 month for a sprocket!!!! those chauvinistic spanisch don`t want parts go out the country.


from Jared i received some parts ,very good correct handling!!
i forgot to thank jared for that; Jared thanks!!

[dutchtwinshock]

Some else might like to confirm this but I think the 250/360 Cappra rod is the  same. The different stroke comes from different big end positioning on the crank (longer stroke).

yes the 250VB/VE/360 rods are the same (124mm)the 250VF/VG went back to 116mm same as the older 250    (maybe i am wrong)
but to achieve the stroke for the 414 they put the bigend hole to the limmits isn`t?

[mx250]

i asked Kevin breedom already, he had for the 360 only a special competition conrod (italkit),very expensive one (260 pound)witch also need a special piston.

Together with him i came along that ktm 250 conrod witch is exactly the same as the montesa 360 conrod.

Which Kattie rod kit?

KTM    250cc T/Stroke W/Cooled Model 84 (Comp)    125    22    29    16    22    60    18x22x25    22x29x16    BC2043S    T/O    £75.79

Montesa          360 Special Competition Rod            124    22    28    16    22    64.4    18x22x22    22x28x16    BC5098R    T/O    £206.04

.... those chauvinistic spanisch don`t want parts go out the country.

I've had the same impression during my attempts to deal with them  - and then the cost of postage became a 'deal killer' 

[dutchtwinshock]

I receved this from Kevin Breedom:

"Hello Marten, the BC 2045 Ktm rod rod would fit very well with a thicker base gasket"

 the Bc 2045 is another one from a 1978 ktm 250 .

you see the bigend side is 29 against 28 from the monty rod.

strange enough on the pdf from rectivicados bellavista stands a montesa 360 rod with a big end hole 29mm

i must searging for the link

[mx250]

I receved this from Kevin Breedom:

"Hello Marten, the BC 2045 Ktm rod rod would fit very well with a thicker base gasket"

 the Bc 2045 is another one from a 1978 ktm 250 .

you see the bigend side is 29 against 28 from the monty rod.

KTM    400cc T/Stroke (Comp)                                    125    22    29    16    22    64.5    18x22x25    22x29x16    BC2045    T/O    £83.86

Montesa               360 Special Competition Rod            124    22    28    16    22    64.4    18x22x22    22x28x16    BC5098R    T/O    £206.04

A bit of difference between £83.86 and £206.04  .

Standard piston works with both I take it.



The 29 vs 28, which is 'C' is fairly critical i would have thought. You would need a blood big press to get that into a 28mm hole in the web  .

[dutchtwinshock]

 I've had the same impression during my attempts to deal with them  - and then the cost of postage became a 'deal killer' 


[/quote]

My father(dutch)  lived there for 20 years and i born there and lived there also 4years.before we came back to the Netherlands
they are extreem chauvinistic there are still some spanisch that believe the sun never goes under/down in Spain because Spain is so big.
THe Armada lost the battle because the ships were to tall

But when Ossa comes this year with a new 250 DFI enduro....I want one!!!

[dutchtwinshock]

I receved this from Kevin Breedom:

"Hello Marten, the BC 2045 Ktm rod rod would fit very well with a thicker base gasket"

 the Bc 2045 is another one from a 1978 ktm 250 .

you see the bigend side is 29 against 28 from the monty rod.

KTM    400cc T/Stroke (Comp)                                    125    22    29    16    22    64.5    18x22x25    22x29x16    BC2045    T/O    £83.86

Montesa               360 Special Competition Rod            124    22    28    16    22    64.4    18x22x22    22x28x16    BC5098R    T/O    £206.04

A bit of difference between £83.86 and £206.04  .

Standard piston works with both I take it.

Sorry i was mistaken with ktm 250  it is a 400 indeed

[dutchtwinshock]

http://www.rectificados-bellavista.com/BIELAS.PDF

look for BM6660.01001 and this one has C-29mm

[montynut]

Some else might like to confirm this but I think the 250/360 Cappra rod is the  same. The different stroke comes from different big end positioning on the crank (longer stroke).

yes the 250VB/VE/360 rods are the same (124mm)the 250VF/VG went back to 116mm same as the older 250    (maybe i am wrong)
but to achieve the stroke for the 414 they put the bigend hole to the limmits isn`t?

I believe the VB360 and 250 had the same Conrod and stroke. I believe the VB250/360 & VE-VG250 have the same stroke but the VE-VG250 have a shorter rod as pointed out above.
You need to be careful as the conrod thrusts for the Montesa engines are at the little end not the big end like most engines. This can be overcome by machining the crank halves I believe.

[montynut]

I receved this from Kevin Breedom:

"Hello Marten, the BC 2045 Ktm rod rod would fit very well with a thicker base gasket"

 the Bc 2045 is another one from a 1978 ktm 250 .

you see the bigend side is 29 against 28 from the monty rod.

KTM    400cc T/Stroke (Comp)                                    125    22    29    16    22    64.5    18x22x25    22x29x16    BC2045    T/O    £83.86

Montesa               360 Special Competition Rod            124    22    28    16    22    64.4    18x22x22    22x28x16    BC5098R    T/O    £206.04

A bit of difference between £83.86 and £206.04  .

Standard piston works with both I take it.



The 29 vs 28, which is 'C' is fairly critical i would have thought. You would need a blood big press to get that into a 28mm hole in the web  .

Does the conrod bigend eye dia matter as long as the ID of the bearing and therefore the pin OD are correct? Just asking

[cappra]

The VB 250/360 and the 414 all use the same rod.  Not sure why you
would have to use the special piston if using the Italkit rod kit.  I sell the
this rod kit for $225. USD.   The main problem I have is that the upper rod
bearing is the incorrect length as used on the VB.  Can't seem to find the
correct bearing anywhere.